What is water brought back to earth in the form of?

In the context of the neural impulse, which of the following is true about the depolarization of neuron membranes?

Im is in a crowd of people at the mall looking for his girlfriend tammy, who was supposed to meet him for dinner. jim realizes tammy is across the room as he catches a whiff of her overpowering perfume, 'paris #6'. which process explains why jim is able to smell the perfume?

When lactate builds up in a runners muscles it causes a burning sensation what causes this to occur