I need some ideas for experiments that show the process of evolution by natural selection. if this could be answered asap that would be super helpful!!

Aneuron is stimulated with an electric pulse. the action potential is detected at a point 3.70 cm down the axon 0.0052 s later.when the action potential is detected 7.20 cm from the point of stimulation, the time required is 0.0063 s. what is the speed of the electric pulse along the axon? (why are two measurements needed instead of only one? )

As a small change in a person's dna can cause a genetic disorder

About __ of the mass of the cell is water