The geological time scale represents the history of what?

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? )

The negative impacts of nonnative species generally outweigh the positive impacts

Approximately percent of the energy created by cell metabolism is used by the body to carry on its normal functions, such as respiration, digestion, reproduction, muscular movement, circulation, and cellular regrowth.