In order to determine what proportion of desks in each classroom should be lefthanded, the administration wants to know what proportion of students at Hope College are left-handed. In a preliminary sample of 12 students, 2 of them are lefthanded. (a) If they want the quick-and-dirty 95% confidence interval for the true proportion of all students who are left-handed to have a margin of error of less than 3%, about how large of a sample will they need?