Suppose, at a local movie theater, the amount of money that a man spends at the concession has an average of 17 dollars and a standard deviation of 4.7 dollars. As well, the amount of money that a woman spends at the concession has an average of 12 dollars and a standard deviation of 3.5 dollars. (a) What is the expected difference in the amount spent by a man and a woman at the concession? (b) What is the standard deviation for this difference? (Round your answers to four decimal places, if needed.) (c) What is the expected total amount spent by a man and a woman at the concession? (d)What is the standard deviation for this total amount? (Round your answers to four decimal places, if needed.)