Calculate the stock expected return-standard deviation

Question

Problem: A stock’s return has the following distributions:

Demand for the           Probability of This     Rate of Return
Company’s Products    Demand Occurring    if This Demand Occurs

Weak                                    0.1                     (50%)
Below Average                      0.2                      (5)
Average                                0.4                      16
Above Average                      0.2                       25
Strong                                   0.1                       60
                                            1.0

Calculate the stock’s expected return, standard deviation, and coefficient of variation.