Oxygen, carbon, and hydrogen
Answer:
Horses have 64 chromosomes and donkeys 62, so when the two breed their mule offspring ends up with 63. Because this is an odd number, it's impossible for them to divide evenly into two. That means the mule cannot produce sperm and egg cells that carry exactly half the animal's chromosomes, as should happen.Aug 28, 2018
Answer: Because scientists often repeat one or more steps several times.
Explanation: The scientific method is described as nonlinear because scientists often repeat one or more steps several times. The correct option among all the options that are given in the question is the second option or option "b".