Calcium has 20 electrons. how many electrons are in the outer shell?
a. 0
b. 2
c. 6
d. 8

2

Explanation:

For the first 20 elements, the first energy level can hold a maximum of two electrons, the second energy level can hold a maximum of 8 and the third energy level can hold a maximum of 8. Calcium has 20 electrons, so we put two in the first energy level, 8 in the second, 8 in the third and we are left with two for the fourth energy level.

Ca: 2,8,8,2

yes it is balanced

a rain shadow is a dry region of land on the side that is protected against the prevailing winds of a mountain range. the prevailing winds are the winds that occur most of the time in a particular place of the earth

prevailing winds carry air toward the mountain range. as the air rises up over a mountain range, the air cools, water vapor condenses, and clouds form. on this side of the mountains, called the windward side, precipitation falls in the form of  rain  or snow. this dry air produces a  rain shadow.