Is melting butter a physical or chemical change

Plz ! cattle ranchers and dairy farmers rarely allow all of their animals to reproduce instead they practice selective breeding and only encourage the reproduction of animals with specific features. which of the following cows would a dairy farm most likely choose to reproduce? a. a cow that makes a lot of milk. b. a cow that can run quickly. c. a cow with a think, soft fur. d. a cow with large, strong hooves.

Ialready know the answers to these questions and they are on the attachment. but i just need to know why that answer is the correct one. plz asap! this is for a report that i need to email by 10!

Which label identifies the part of the atp molecule that changes when energy is released in the cells of all living things