Just couple questions that I need help wth thanks.

Question 5.5 The number of arrivals per minute at a bank located in the central business district of a large city recorded over a period of ZDEI minutes, with the following results: Arrivals Frequency H D _ __ . Algal-n \"~1th a. Compute the expected number of arrivals per minute. b. Compute the standard deviation. Question 5.7 You are trying to develop a strategy for investing in two different stocks. The anticipated annual return for a $1,000 investment in each stock under four different eoonomic conditions has the following probability distribution. Probability Economic Condition Stock X Stock Y Recession Moderate Growth \" Slow Growth '- _E- 200 Compute the: a. Expected Return for Stock X and Stock Y. b. Standard Deviation for Stock X and Stock Y c. Would you invest in Stock X or Stock Y? Explain