I dont know how to do this i know for the a expanded form but the rest is confuse

Farnesene is a sesquiterpene. how many different isomers arising from double-bond isomerizations are possible? g

What is the ratio of the change in y-values to the change in x-values for this function? a) 1: 13 b) 2: 5 c) 5: 2 d) 13: 1

The parabola y = x² - 4 opens: a.) up b.) down c.) right d.) left