Earth is approximately spherical in shape like all planets and stars. Earth is composed mostly of rock. Three-fourths of its surface is covered by a relatively thin layer of water (some of it frozen), and the entire planet is surrounded by a relatively thin blanket of air.
Answer: exercise secretes a hormone called endorphins which makes you happy
I’m guessing the answer is 4
Excitatory neurotransmitter? This question is too vague.
