An aquifer is a(n)
a. underground layer of rock or sediment that holds water.
b. well in which water rises because of pressure.
c. type of hot spring from which the water periodically erupts.
d. place where groundwater bubbles or flows out of cracks in the rock.

An aquifer is an underground layer of rock or sediment that holds water. The correct answer is A.

a. underground layer of rock or sediment that holds water.

Explanation:

An aquifer is a natural underground area that has larger quantities of water and fills the space between the ricks and the sediments and is separated by a confined and an unconfined layer of rocks. This confined layer is overlaid by the impermeable rock or an aquitard and restricts the water within the aquifer. While an unconfined aquifer is not overlaid by a layer of impermeable rocks or soil.

2. x2 + 8x + 12 = 0 to prove: x = -6 or x = -2