What's the property to (x/y)^3=x^3/y^3

Given: hf || jk; hg ? jg prove: fhg ? kjg to prove that the triangles are congruent by asa, which statement and reason could be used as part of the proof? fgh ? kgj because vertical angles are congruent. jkg ? hfg because vertical angles are congruent. fhg ? jkg because right angles are congruent. hfg ? kjg because alternate interior angles are congruent.

[10 points, algebra 2-simplifying complex fractions]according to my answer key the restrictions are -1 and 4. but why not positive 1?

Iwill give ! if m∠a=59 and m∠3=81°, what is m∠b? m∠b= _[blank]_°