This picture should help, i graphed it for you! : )
Factors that are 1 and itself.
A
C
D
E
F
B should be the obvious no-no
The percent change from 36 to 63 is 63/36=1.75 (multiply by 100 to get a percentage) 175%
The percent change from 63 to 36 is 36/63=0.571=57.1%
A square root is a number times itself .
for example 2x2 is a square root .
so, any number times itself is a square root