Answer:
x=10
Step-by-step explanation:
The answer would be the first choice. 
Explanation: The reason for this is that the question was pretty much just asking what the area of the resulting two-dimensional cross section would be -the shape in gray- (which can be found by using the formula
. To add on, since the dimensions of the shape are already given (5 and 3) all you've to do is multiply: 3*5=15
That's how you get to the answer.
Answer: Option 'D' is correct.
Step-by-step explanation:
Since we have given that
First term = 13
Increase each time = 20
Number of clients = 25
So, it forms an arithmetic progression:
So, 25 th term would be

Hence, list would look like 13,33,............493.
Therefore, Option 'D' is correct.
9x-(2x+8)
Distribute the - to both 2x and 8
9x-2x-8
simplify
7x-8