Anelephanthastohavethickerlegsrelativetoitsweightbecausethestrengthoflegsareproportionaltotheircrosssectionarea,whichisrelatedtothesquareofsize,whereastheweightisroughlyproportionaltothecubeofsize.

Please segment the words:
An elephant has to have thicker legs relative to its weight because the strength of legs are proportional to their cross section area, which is related to the square of size, whereas the weight is roughly proportional to the cube of size.