Side of a square = 10 m; Perimeter= CAN SOMEONE PLS TELL ME THE ANSWER WITH AN EXPLANATION?!

The brain volumes (cm cubed) of 50 brains vary from a low of 904 cm cubed to a high of 1488 cm cubed. use the range rule of thumb to estimate the standard deviation s and compare the result to the exact standard deviation of 175.5 cm cubed, assuming the estimate is accurate if it is within 15 cm cubed

(x-5)1/2+5=2 what is possible solution of this equation

*segment an is an altitude of right ? abc with a right angle at a. if ab = 2root 5 in and nc = 1 in, find bn, an, ac.