2 a Students want to determine if there is a significant correlation between the amount of free time spent using their cell phones and their GPA Determine th type of study used in each examples a c below Part A a 50 students were selected randomly and asked about the number of hours they spent in a week using their phones and their current GPA Part B b The GPA s of 50 randomly selected students that do not own cell phones were recorded and compared to 50 randomly selected students with cell phones and their GPA s Part C c Ten students with poor GPA s had their cell phones restricted for a year After the year their current GPA was compared with their GPA from the previous year Part D du Explain your reasoning