Consider the following information on returns and probabilities:

State Probability X Z

Boom .25 15% 10%

Normal .60 10% 9%

Recession .15 5% 10%

What is the standard deviation for a portfolio with an investment of $6,000 in asset X and $4,000 in asset Z?

A) 6.10%

B) 8.15%

C) 1.85%

D) 3.00%

E) 5.18%