Question

which alcohol and carboxylic acid would produce isoamyl propanoate by Fischer esterification

Answer 1

I'm not an organic chemist so I must figure these things out as I go. It is done this way. Think about how one makes ethyl acetate.
acetic acid + ethyl alcohol = ester.

CH3COOH + C2H5OH => CH3COOC2H5 so the ethyl of ethyl acetate comes from the alcohol and the acetate part of ethyl acetate comes form the acid.
To make isoamyl propanoate, you want propanoic acid and isoamyl alcohol.