According to Investment Digest(Diversification and the Risk/Reward; Winter 1994 1-3), the mean of the annual return for common stocks from 1926 to 1992 was 16.5%, and the standard deviation of the annual return was 19%.

In later parts of the question we will ask:

a. What is the probability that the stock return are greater than 0%?

b. What is the probability that the stock returns are less than 18%?

For this part, answer the following question:

What is the value of the test statistic (Z, t, or F) for each part(Round to 2 decimal digits).

A. -0.87 in part a, -0.06 in part b

B. -067 in part a, 0.06 in part b

C. -0.87 in part a, 0.08 in part b

D. 0.67 in part a, 0.08 in part b