Please help and explain the answer

3a- the 1st one

Explanation:

3b- when comparing the genetic codes and looking for differences, the scientists could find the types of mutations that possibly happened, or different changes in the marine snails due to the rise of plastic waste in oceans.

the most common energy conversion is from kinetic energy to potential energy, and then from potential energy to kinetic energy.

later on comes the heat energy, mechanical energy, and other energy conversions.

this energy conversion is so common that we can find it in our day to day lives as well.

- one of the most common energy conversions involves the changing of potential energy to kinetic energy or kinetic energy to potential energy

the fossil record provides evidence of a common ancestor to many species.