I just need help with (c)

mple Question o: probability models Suppose that x represents the number of cars sold at a dealership in a randomly selected single day. The probability distribution of x is given in the table below. X 7 10 p(xx) 0.04 0 09 0.17 0.29 0.20 0.14 0.07 (a) Find the population mean p. E(X) - Hx = > x . p(x) all x (b) Calculate the population variance q 2 02 - E(X2) - 142 - x2p(x) -12 all x (c) Suppose 20 observations are taken independently from this distribution and the sample mean X of these observations is recorded. What would be the mean and standard deviation for the sampling distribution of X? 17