The reabsorption of neurotransmitters by a terminal button is called:

The answer to this question would be reuptake

Reuptake is a reabsorption of the neurotransmitters that had been released. Reuptake is important because if the neurotransmitter isn't removed, they can repeatedly induce a signal.
Some drug works by inhibiting this reuptake mechanism like serotonin reuptake inhibitor. By doing this, the drug will increase the number of the neurotransmitter since it won't reabsorbed.

By using internet

1.989×10^30 kg is the weight of the sun.