<span><span> Answer: </span>Acetylcholine</span>
Acetylcholine<span> is a neurotransmitter, which is a chemical released by the axons of a motor neuron which causes muscles to contract. It has other functions: activates pain responses and regulates endocrine and REM sleep functions. Deficiencies in acetylcholine cause muscle weakness.</span>
B. by evaporation. this Is how rocks are created