4. (12 pts) If 60% of all women are employed outside the home, find the probability that in a sample of 20 women a. Exactly 15 are employed (4 decimals) b. At least 10 are employed (4 decimals) C. At most 5 are not employed outside home (4 decimals) d. Find the mean, variance and standard deviation of the women who are employed outside the home (1 decimal) (Hint: Use Binomial distribution)