. The element with the following electronic configuration, 1s2, 2s2, 2p6, 3s2
3p is (a) chlorine (b) argon ​

Explanation:

(a) Chlorine the first row Is 1s the second is 2s followed by 2p...etc as Chlorine has 17 electrons

c- cold periods in earth's history during which glaciers covered much of the surface.

explanation:

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.