which of these is the most ethical reason for using a simulation rather than an experiment with live animals

How many chromosomes are in a gold fish?

Why is the theory of evolution important? it disproves all other theories about how life began. it provides a topic for debate. it is a unifying concept in biology. it explains how life began. i know for sure, it is not "it is a unifying concept in biology."

If a strand of dna has 35% thymine. what is the percentage of cytosine, adenine, guanine?