Why is it important for the mass to be measured before measuring the volume.​

In this experiment the mass must be measured first because to determine volume water displacement is what is being measured. ... The reason for this is some solids will float on the water. Therefore the object's density is less dense than the water.

a. decomposes use carbon from dead organisms as fuel for cellular respiration, returning carbon dioxide back into the atmosphere.

the answer that best describes the relative refractory period in the neuron is the resting membrane potential is restored, but concentrations of sodium and potassium are not restored to their original state.

the refractory period is the time during which another stimulus given to the neuron will not lead to a second potential. thus, because na+ channels are inactivated during this time, additional depolarizing stimuli do not lead to new action potentials.  

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