1. There are currently seven statistics classes being taught this semester at Wilmington College. The following data represent the number of students in each class. 20 25 18 32 22 30 28 Calculate the variance of this population. 2. The following data represent the time between customer arrivals, in minutes, at a drive-thru for a fast food restaurant. 2 4 1 0 6 4 1 Calculate the standard deviation of this sample. 3. The following data represents the number of credit cards owned by a random sample of eight adults. 0 5 1 6 5 2 2 7 Calculate the standard deviation of this sample