49cm Would be your answer, sorry for the late reply
I think it is -5,-4,-1/4, 1.75, 6.2, 9, 18 1/2, 21
Don't you mean 66 divided by eight?
That would equal 8.25, or 8 remainder 2.
if you did mean 8 divided by 66, your answer is not one of your choices.
The power of 25 on the variable z needs to be changed. It has to be divisible by 3.