The answer is 78.5 you can get this by multiplying pi by the radius which is 5 then square it and you get 78.5
Answer:

Step-by-step explanation:
we know that
<u><em>Combinations</em></u> are a way to calculate the total outcomes of an event where order of the outcomes does not matter.
To calculate combinations, we will use the formula

where
n represents the total number of items
r represents the number of items being chosen at a time.
In this problem

substitute

simplify



1.534
2.168
3.230
4.408
5.78
6.642
7.3
81016
9.1900
10.8 times (40 plus 5)
You can simply put the equation as 9x = 36 and divide by 9, then x = 4