A firm has the NPV of a project based on three possible economic conditions and their probabilities given below. The expected NPV is $35 million. What is the standard deviation for the project's NPV?

Economic Condition	Probability	NPV ($million)
Recession	.70	22
Boom	.20	74
No Change	.10	48

A) 22.01

B) 20.96

C) 19.91

D) 22.85

E) 19.49