And for a given substance occur at the same temperature.
a. melting, freezing
b. melting, boiling
c. freezing, evaporation
d. boiling, freezing

Melting and freezing for a given substance occurs at the same temperature. Because the temperature at which the solid starts to melt is also the temperature at which the liquid starts to freeze. They are at chemical equilibrium.

smooth muscle is composed of involuntary muscles found within the walls of organs and structures such as the esophagus, stomach, intestines, and blood vessels. those muscles push materials like food or blood through organs. unlike skeletal muscle, smooth muscle can never be under your control.