The standard deviation of 36,18,12,10 and 9 is 10
Based on my calculation i know for sure F
would equal 10
The question is an illustration of related rates.
The rate of change between you and the ball is 0.01 rad per second
I added an attachment to illustrate the given parameters.
The representations on the attachment are:

---- the rate

First, we calculate the vertical distance (y) using tangent ratio

Substitute 100 for x


Differentiate both sides with respect to time (t)

Substitute values for the rates and 

This gives


Divide both sides by 2


Hence, the rate of change between you and the ball is 0.01 rad per second
Read more about related rates at:
brainly.com/question/16981791
Since we have 2 numbers, we'll be square rooting.
All we have to do to find the mean is multiply & square root the products.
30 × 6 = 180

You can use the same process and check my answer if you'd like; I rounded the square root, so you may get a different answer.