39. The normal amount of lead in a certain water supply is 1.5 × 10-5 milligrams per liter. Today, when the water was tested, the lead level found was exactly 100 times as great as the normal level, still well below the Environmental Protection Agency’s action level. What concentration of lead, in milligrams per liter, was in the water tested today ?

Answer and Explanation

Your Answer is

Correct Answer is D

Explanation

From the meaning of the question: the content of the compound in the tested water quality sample is 100 times the normal content, and the normal content is known, then the content in the test sample is: 1.5×10-5 × 100 = 1.5×10-3, which is the answer D.