4. The cost of purchasing songs from a particular online service can be found by using the following equation: c= 1. 390 + 3. 50 Where c represents the total cost and d represents the number of songs downloaded. If Josh spent a total of $20. 18, how many songs did he download? A 12 B 6 C 11 D 7​

a. For the function, the interval for which f is concave down on [0,2π] is (π/4, 5π/4).

CCUP: (0, π/4) and (5π/4, 2π)

CCDOWN: (π/4, 5π/4)

b. The coordinates of the points of inflection are (π/4, 2.45) and (5π/4, -5.95).

a. To find the intervals for which f is concave up and concave down on [0,2π], we need to determine the second derivative of the function f(x):

f(x) = -5.5 sin x + 5.5 cos x

f'(x) = -5.5 cos x - 5.5 sin x

f''(x) = 5.5 sin x - 5.5 cos x

To find where f is concave up (CCUP), we need to find where f''(x) > 0. Thus, we solve the inequality:

5.5 sin x - 5.5 cos x > 0

sin x > cos x

This inequality holds for 0 < x < π/4 and 5π/4 < x < 2π. Therefore, the intervals for which f is concave up on [0,2π] are (0, π/4) and (5π/4, 2π).

To find where f is concave down (CCDOWN), we need to find where f''(x) < 0. Thus, we solve the inequality:

5.5 sin x - 5.5 cos x < 0

sin x < cos x

This inequality holds for π/4 < x < 5π/4. Therefore, the interval for which f is concave down on [0,2π] is (π/4, 5π/4).

Thus, we have:

CCUP: (0, π/4) and (5π/4, 2π)

CCDOWN: (π/4, 5π/4)

b. To find the coordinates of any points of inflection for f on [0,2π], we need to find where the concavity changes, i.e., where f''(x) = 0 or is undefined. Thus, we solve the equation:

5.5 sin x - 5.5 cos x = 0

sin x = cos x

This equation holds for x = π/4 and x = 5π/4.

To determine the concavity at these points, we can examine the sign of f''(x) in the intervals surrounding these points:

For x in (0, π/4), f''(x) < 0, so f is concave down.

For x in (π/4, 5π/4), f''(x) > 0, so f is concave up.

For x in (5π/4, 2π), f''(x) < 0, so f is concave down.

Therefore, the points of inflection for f on [0,2π] are (π/4, f(π/4)) and (5π/4, f(5π/4)).

To find the coordinates of these points, we can substitute π/4 and 5π/4 into the original function:

f(π/4) = -5.5 sin(π/4) + 5.5 cos(π/4) = -2.75 + 5.5/√2 ≈ 2.45

f(5π/4) = -5.5 sin(5π/4) + 5.5 cos(5π/4) = -2.75 - 5.5/√2 ≈ -5.95

Therefore, the coordinates of the points of inflection are (π/4, 2.45) and (5π/4, -5.95).

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The acceleration is 2 m/s²

The first step is to write out the parameters given in the question

Acceleration is the rate at which an object changes its velocity over time.

The formula to calculate the acceleration is v²= u² + 2as10²= 0² + 2(a)(25)100= 2a(25)100= 50a

Divide both sides by the coefficient of a which is 50

100/50 =  50a/50

a= 2

Hence the acceleration of the object is 2 m/s²

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Answer:

225

Step-by-step explanation:

since the ratio is 4 to 5 and the number of union workers are 100 you divide the number of union workers by their respective ratio which is four then multiply that by the 5

Herberto travelled through Amusement Park (AP), City Park (P), Landmark (L), High School (HS), City Hall (CH).

Herberto can take the following path to travel from the amusement park (AP) to the city hall (CH):

Amusement Park (AP) -> City Park (P) -> Landmark (L) -> High School (HS) -> City Hall (CH)

This path takes him through the city park, then to the landmark, followed by the high school, and finally to the city hall.

Please note that without a specific map or layout of Knappville, there could be multiple valid paths from the amusement park to the city hall. The path provided above is just one example.

When Herberto travels from the amusement park to the city hall, he can choose various paths depending on the specific layout of Knappville. The path mentioned earlier is just one example, but the actual paths could differ based on the town's infrastructure and the locations of the landmarks.

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Answer:

4,6,[tex]\sqrt{52} \\[/tex]

Step-by-step explanation:

Area of right triangle= base x height/2=12, but if we remove the division then it's:

base x height=24

factors of 24= 6,4  8,3 24,1 and 12,2

we have the rule that "One leg of the triangle measures one and a half times the length of the other leg." and the pair that matches that is 6 and 4.

So leg a=4 and leg b=6. Using the Pythagorean theorem(a^2+b^2=c^2) we have:

4^2+6^2=c^2=16+36=52 so the answer is 4,6,[tex]\sqrt{52} \\[/tex]

This is a linear equation in slope-intercept form, where the slope (m) is 50 and the y-intercept (b) is 62.

Since the milepost increases by a fixed amount of 50 for every hour that they drive, the most appropriate type of equation to describe this relationship is a linear equation.

A linear equation has the form y = mx + b, where m is the slope of the line and b is the y-intercept. In this case, the slope is 50, since the milepost increases by 50 for every hour of driving, and the y-intercept is 62, since they start at milepost 62.

Therefore, the equation that represents Abby's relationship between the milepost they pass, y, and the number of hours they drive, x, is:

y = 50x + 62

This is a linear equation in slope-intercept form, where the slope (m) is 50 and the y-intercept (b) is 62.

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The average number of customers in the shop is 7.5

The average number of customers in the shop can be calculated using the M/M/2 queuing model. In this model, we assume that the arrivals follow a Poisson distribution, and the service times follow an exponential distribution.

The subscript "2" in M/M/2 refers to the fact that there are two servers or service channels available.

Using Little's Law, the average number of customers in a stable system is equal to the product of the arrival rate and the average time spent in the system.

Thus, to calculate the average number of customers in the shop, we need to find the average time spent in the system.

The average time spent in the system can be calculated as the sum of the average time spent waiting in the queue and the average time spent being served. Using the M/M/2 queuing model,

the average time spent waiting in the queue can be calculated as [tex](λ^2)/(2μ(μ-λ))[/tex], where λ is the arrival rate and μ is the service rate. In this case, λ=3 and μ=1/2 since there is one barber who can serve one customer at a time.

Thus, the average time spent waiting in the queue is [tex](3^2)/(21/2(1/2-3))[/tex] = 9/4 hours. The average time spent being served is the mean service time, which is 1/4 hour. Therefore, the average time spent in the system is 9/4 + 1/4 = 5/2 hours.

Finally, using Little's Law, the average number of customers in the shop is λ times the average time spent in the system, which is 3*(5/2) = 15/2 or 7.5 customers.

However, since the shop can only accommodate at most two customers at a time, the actual number of customers in the shop would be either one or two.

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The formula to calculate surface area is 2(Length × Width) + 2(Length × Height) + 2(Width × Height) and the length, width, and height of the sandbox is required to calculate rectangular area.

To determine how much sand your cousin will need to fill the rectangular prism-shaped sandbox, we first need to calculate its volume. To do this, we need the dimensions of the sandbox (length, width, and height). The formula for the volume of a rectangular prism is:

Volume = Length × Width × Height

Once we have the volume, we can determine the amount of sand needed to fill the sandbox in cubic units.

To find out how much paint is needed to paint all six surfaces of the sandbox, we need to calculate its surface area. The formula for the surface area of a rectangular prism is:

Surface Area = 2(Length × Width) + 2(Length × Height) + 2(Width × Height)

Once we have the surface area, we can determine the amount of paint required, usually measured in square units. Note that the amount of paint needed also depends on the coverage rate of the paint, which is typically listed on the paint container.

Please provide the dimensions of the sandbox (length, width, and height) so I can provide specific calculations for the sand and paint required.

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Q to R transformation: Reflection, translation.

The transformation of Figure Q to Figure R involves a combination of reflection and translation. Firstly, Figure Q was flipped over the y-axis, which means that all the points of the figure on the left side of the y-axis were moved to the right side and vice versa.

Then, the figure was translated 6 units to the right, resulting in Figure R. Secondly, Figure Q was flipped over the x-axis, which means that all the points of the figure above the x-axis were moved below it and vice versa.

Finally, the figure was translated 4 units to the right, resulting in Figure R. These transformations are important in geometry as they allow us to create new figures that are related to the original ones.

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Answer:

D

Step-by-step explanation:

The equivalent expression is $\left(\dfrac{4^{3}}{5^{-2}}\right)^{5} = 102400000000000000000$.

We can simplify the expression inside the parentheses first:

\begin{aligned} \frac{4^3}{5^{-2}} &= 4^3 \cdot 5^2 \ &= (2^2)^3 \cdot 5^2 \ &= 2^6 \cdot 5^2 \ &= 2^5 \cdot 2 \cdot 5^2 \ &= 2^5 \cdot 10^2 \ &= 3200 \end{aligned}

Now we can substitute this value into the original expression and simplify further:

\begin{aligned} \left(\frac{4^3}{5^{-2}}\right)^5 &= (3200)^5 \ &= (2^8 \cdot 5^2)^5 \ &= 2^{40} \cdot 5^{10} \ &= (2^4)^{10} \cdot 5^{10} \ &= 16^{10} \cdot 5^{10} \ &= (16 \cdot 5)^{10} \ &= 80^{10} \ &= 102400000000000000000 \end{aligned}

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If the area of the hallway is 250 square feet, it would cost $625 to carpet the hallway with $2.50 per square foot carpet.

To find the cost of carpeting the hallway, we need to know the area of the hallway first. Let's assume that the length of the hallway is 50 feet and the width is 5 feet.

The area of the hallway = length x width
= 50 feet x 5 feet
= 250 square feet

Now that we know  we can find the cost of carpeting it.

Cost of carpeting = area x cost per square foot
= 250 square feet x $2.50 per square foot
= $625

Therefore, it would cost $625 to carpet the hallway with $2.50 per square foot carpet.

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Answer:

the answer is 8

Step-by-step explanation:

it is because if you take your 9 fingers and remove 1 finger it will be 8

The probability that someone went to either homecoming or prom is 1, or 100%.

To find the probability that someone went to either homecoming or prom, we need to add the number of students who went to each dance and then subtract the number of students who went to both dances (as they would have been counted twice in the first step).

So, the total number of students who went to either homecoming or prom is:

250 + 300 - 200 = 350

Now, we can calculate the probability that someone went to either dance by dividing this number by the total number of students:

P(homecoming or prom) = 350 / (250 + 300 - 200) = 350 / 300 = 1.17

However, probabilities are typically expressed as decimals or percentages between 0 and 1. Since it's impossible for someone to have a probability greater than 1, we can conclude that there is an error in our calculation. This is likely because we made a mistake when adding or subtracting the number of students.

To correct this, we need to double-check our work and make sure we have the correct numbers. Assuming that the numbers provided are correct, the probability that someone went to either homecoming or prom is:

P(homecoming or prom) = 350 / (250 + 300 - 200) = 350 / 350 = 1

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Katy and Colleen each choose a number from 3, 6, or 8. If the sum is even, Katy pays Colleen the sum in dimes, and if odd, Colleen pays Katy the sum in dimes. There are 9 possible outcomes with payments ranging from 3 to 16 dimes.

If Katy writes down 3, then Colleen has two choices, either write down 3 to make the sum even or 6 to make it odd. If Colleen writes down 3, the sum is even, and Katy pays Colleen 6 dimes. If Colleen writes down 6, the sum is odd, and Colleen pays Katy 3 dimes.

If Katy writes down 6, then Colleen has two choices, either write down 3 to make the sum odd or 8 to make it even. If Colleen writes down 3, the sum is odd, and Colleen pays Katy 6 dimes. If Colleen writes down 8, the sum is even, and Katy pays Colleen 14 dimes.

If Katy writes down 8, then Colleen has two choices, either write down 3 to make the sum odd or 6 to make it even. If Colleen writes down 3, the sum is odd, and Colleen pays Katy 8 dimes. If Colleen writes down 6, the sum is even, and Katy pays Colleen 14 dimes.

Therefore, the possible outcomes and their corresponding payments are

3 + 3: odd, Colleen pays Katy 3 dimes

3 + 6: even, Katy pays Colleen 6 dimes

3 + 8: odd, Colleen pays Katy 8 dimes

6 + 3: odd, Colleen pays Katy 6 dimes

6 + 6: even, Katy pays Colleen 14 dimes

6 + 8: even, Katy pays Colleen 14 dimes

8 + 3: odd, Colleen pays Katy 8 dimes

8 + 6: even, Katy pays Colleen 14 dimes

8 + 8: even, Katy pays Colleen 16 dimes.

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Here is the expected number of broken machines or tanks and K is the total number of tanks. So (K-L) gives the number of tanks in working condition.

The number of repairmen (R) needed to have an average of at least 180 tanks working is to be determined. Thus as observed from the results obtained for one-way data table, the value of R such that (K-L) is at least 180 is R = 11 repairmen

The Expected number of broken or bad machines (L) is

[tex]L=\sum j\pi_i[/tex]

The Expected number of machines waiting for service (1) is

[tex]L=\sum (j-R)\pi_i[/tex]

An expected number of words is often used as a guideline to ensure that the content is neither too long nor too short. In this case, the expected number is 150 words. A 150-word piece of writing can be considered a short composition. It is long enough to convey a basic idea or message, but not so long that it becomes tedious to read. This length is often used in blog posts, news articles, and social media updates.

When writing a 150-word piece, it is important to make every word count. The writing should be clear and concise, with each sentence contributing to the overall message. It may also be helpful to outline the main points before starting to write to ensure that the piece stays focused.

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The factored form of the polynomial x⁴ - 2x³- 16x² + 2x + 15 is [x³(x - 2) - (4x + 3)(4x - 5)].

Factoring the polynomial?

x⁴- 2x³ - 16x² + 2x + 15.

First, look for any common factors among the terms. In this case, there are none.

Next, try factoring by grouping. To do this, group the first two terms and the last three terms: (x⁴ - 2x³) - (16x² - 2x - 15).

Factor out the greatest common factor from each group: x³(x - 2) - 1(16x² - 2x - 15).

Now, we have a difference of two expressions, but there isn't a common factor to factor further. Therefore, we must use other methods to factor the quadratic expression 16x²- 2x - 15.

Factor the quadratic expression using the "ac method." Multiply the leading coefficient (16) by the constant term (-15) to get -240. Find two numbers that multiply to -240 and add up to the linear coefficient (-2). These numbers are 12 and -20.

Rewrite the middle term using the two numbers found: 16x² + 12x - 20x - 15.

Group the terms in pairs: (16x² + 12x) + (-20x - 15).

Factor out the greatest common factor from each group: 4x(4x + 3) - 5(4x + 3).

Factor out the common binomial factor: (4x + 3)(4x - 5).

Now, put everything together: x³(x - 2) - (4x + 3)(4x - 5).

So, the factored form of the polynomial x⁴ - 2x³- 16x² + 2x + 15 is [x³(x - 2) - (4x + 3)(4x - 5)].

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Regarding the second question, the management of Neat Upholsterers may determine whether a person has worked overtime by tracking their hours of work and comparing them to the standard working hours or the overtime policy defined in the employment contract or labor laws. This could involve using time cards, electronic systems, or other methods of tracking employee hours.

Whether this policy is fair or not depends on various factors, such as the specific overtime policy, the industry norms, the labor laws, and the bargaining power of the employees. If the overtime policy is reasonable, transparent, and consistent with the labor laws and the industry standards, and if the employees are compensated fairly for their extra work, then the policy could be considered fair. However, if the policy is exploitative, discriminatory, or violates the legal or ethical standards, then it could be considered unfair.

Answer:

7 + 2x = 3x - 1

3x-2x = 7+1

x = 8

Step-by-step explanation:

The length of a leg of the isosceles trapezoid is 20 units.

To find the length of a leg of the isosceles trapezoid, you can use the Pythagorean theorem. Given the lengths of the bases are 20 and 44, and the length of the altitude is 16, first find the difference between the bases:

44 - 20 = 24

Since the trapezoid is isosceles, the difference between the bases will be equally divided between both legs. Therefore, the horizontal distance for each leg is:

24 / 2 = 12

Now you have a right triangle formed by the leg, altitude, and the horizontal distance. Applying the Pythagorean theorem, let L be the length of the leg:

L^2 = 16^2 + 12^2
L^2 = 256 + 144
L^2 = 400

Taking the square root of both sides:

L = √400 = 20

The length of a leg of the isosceles trapezoid is 20 units.

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Let’s solve this system of equations. From the first equation, we have x = 6 + 2y. Substituting this into the second equation, we get 1/2(6 + 2y) + 3 = y. Solving for y, we get y = -6. Substituting this value of y into the first equation, we get x = 6 + 2(-6) = -6. So the solution to the system of equations is (x,y) = (-6,-6).

With the masses, the value of a and b will be 6 and 5.

The value of m is 6.

The mass of an African elephant is 6,125,000 grams, or about 6 x 10⁶grams. Thus, b = 6.

The mass of a silverback gorilla is 185,000 grams, or about 1.85 x 10⁵grams. Thus, c = 5.

We are told that the mass of the African elephant is about 10 times the mass of the silverback gorilla, where m is an integer.

Let's write this as an equation:

6 x 10ⁿ = 10(1.85 x 10⁵)

Simplifying this equation, we get:

6 x 10ⁿ = 1.85 x 10⁶

10ⁿ = 3.08 x 10⁵

Taking the logarithm (base 10) of both sides, we get:

m = log(3.08 x 10)

Using a calculator, we find that:

m ≈ 5.49

Since m must be an integer, we round up to the nearest integer and get:

m = 6.

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For calls that are 6 minutes less, the rate is $0.70 per minute.

To find the cost of a call that is under 6 minutes, we simply need to use the first part of the rate schedule.

Let's say the call lasts for m minutes. Since m is less than or equal to 6, we can use the first part of the rate schedule, which gives us

c(m) = $0.70 per minute

So the cost of the call is simply the rate per minute times the number of minutes

c(m) = $0.70 × m

For example, if the call lasted 4 minutes, the cost would be

c(4) = $0.70 × 4 = $2.80

Therefore, the cost of a call that is under 6 minutes is simply $0.70 per minute.

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--The given question is incomplete, the complete question is given

" A phone company set the following rate schedule for an m-minute call from any of its pay phones.

c(m)=

{0.70    when m≤6

0.70+0.24(m−6)   when m>6 and m is an integer

0.70+0.24([m−6]+1)    when m>6 and m is not an integer }

what is the cost of a call that is under six minutes?​"--

The radius of ⊙P is also 12, so ⊙Q and ⊙P have the same size. Therefore, they are similar circles.

1. To construct a circle circumscribed about triangle △DEF, we need to find its circumcenter, which is the point where the perpendicular bisectors of the sides of the triangle intersect.

To do this, we first draw the three perpendicular bisectors of the sides of the triangle. The point where these three bisectors intersect is the circumcenter, which we label as C. We then draw a circle with center C and radius equal to the distance between C and any of the vertices of the triangle, such as D.

2. To show that ⊙O and ⊙P are similar, we can use a similarity transformation such as a dilation. We can start by translating ⊙O and ⊙P so that their centers are both at the origin. We can then scale ⊙O by a factor of 12/5 to get a new circle ⊙Q with the same center as ⊙O and a radius of 12.

The radius of ⊙P is also 12, so ⊙Q and ⊙P have the same size. Therefore, they are similar circles. We can then translate ⊙Q back to its original position centered at (−2, 7) to show that ⊙O and ⊙P are similar circles with similarity center at (−2, 7).

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The equations that would be correct with fraction 2/9 are:

81*x=18

45*x=100

900*c=200

Based on the given equation from the question, it can be seen that the fraction that is needed to complete the X is required, that will give the correct answer to each of the equation.

From the question, we can see that if we put X= 2/9 into the space above, we will have the correct solution. which is been performed below.

81*2/9=18

45*2/9=100

900*2/9=200

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The correct statement for p-value in chi-square is : Assuming that each high school has the same absentee rate for each grade level, there is a 2.5 percent chance of finding a test statistic 19.02 or larger, option B.

A test that evaluates how well a model matches real observed data is the chi-square (2) statistic. A chi-square statistic can only be calculated with data that is random, unprocessed, mutually exclusive, obtained from independent variables, and drawn from a sizable enough sample. The outcomes of a fair coin flip, for instance, satisfy these requirements.

To test hypotheses, chi-square tests are frequently employed. Given the size of the sample and the number of variables in the relationship, the chi-square statistic examines the magnitude of any differences between the predicted findings and the actual results.

According to the total number of variables and samples used in the experiment, degrees of freedom are utilised in these tests to assess if a certain null hypothesis can be rejected. Like with any statistic, the results are more trustworthy the greater the sample size.

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Complete question:

A chi-square test for homogeneity was conducted to investigate whether the four high schools in a school district have different absentee rates for each of four grade levels. The chi-square test statistic and p-value of the test were 19.02 and 0.025, respectively. Which of the following is the correct interpretation of the p-value in the context of the test?

A) Assuming that each high school has the same absentee rate for each grade level, there is a 2.5 percent chance of finding a test statistic 19.02 or smaller.

B) Assuming that each high school has the same absentee rate for each grade level, there is a 2.5 percent chance of finding a test statistic 19.02 or larger.

C) Assuming that each high school has a different absentee rate for each grade level, there is a 2.5 percent chance of finding a test statistic 19.02 or larger.

D) There is a 2.5 percent chance that the absentee rate for each grade level at the four schools is the same.

E) There is a 2.5 percent chance that the absentee rate for each grade level at the four schools is different.

To test the convergence of the given infinite series, we can use the Alternating Series Test. The series is in the form: Σ((-1)^n * (arctan(n)/n^2)), for n = 1 to infinity.

The Alternating Series Test requires two conditions to be met:

1. The absolute value of the terms in the series must be decreasing: |a_n+1| ≤ |a_n|.
2. The limit of the terms in the series as n approaches infinity must be zero: lim (n→∞) |a_n| = 0.

For the given series, let's check these conditions: 1.The absolute value of the terms: |arctan(n)/n^2|. Since arctan(n) increases with n and n^2 increases faster than arctan(n), the ratio (arctan(n)/n^2) decreases as n increases. Therefore, this condition is met.

2. Now, we need to check the limit: lim (n→∞) |arctan(n)/n^2|. As n approaches infinity, the arctan(n) approaches π/2, and n^2 approaches infinity.

Therefore, the limit is (π/2)/∞ = 0, so the second condition is also met. Since both conditions are met, the Alternating Series Test confirms that the given series converges.

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                          "Complete question"

Apply Any Appropriate Testing Method To: ∞X N=1 (−1)Narctan N N2

Apply any appropriate Testing Method to:

∞X

n=1

(−1)narctan n

n2

1465 will be the mean monthly salary .The answer is (A) Rs. 1465.

Let the sum of the 12 employees' salaries be S.

Then, the mean monthly salary of the 12 employees is given by:

S/12 = 1450

S = 12 * 1450

S = 17400

If one more person joins with a salary of Rs. 1645, the new sum of the 13 employees' salaries is:

S' = S + 1645

S' = 17400 + 1645

S' = 19045

The new mean monthly salary of the 13 employees is:

S'/13 = 19045/13

S'/13 = 1465

Therefore, the answer is (A) Rs. 1465.

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