I am certain the answer is C. Algebra properties are used in proofs. Postulates are definitely used. And definitions are explanations. So, it is C.
First add the perimeter
3.65m + 2.24m + 2.24m + 3.65m + 2.57m = 14.35 m
then convert meters to centimeters (just move the decimal place two places to the right)
answer is 1,435 cm
I believe it's 9.1 Hope this helps :)