The number of hours in a week (x) that a student spends studying for a test is shown for a group of students in the table below. Use this table to answer parts a) - c). Hours (x) Frequency P(x) 1 4 2 18 3 20 4 8 a) Complete the table to create a probability distribution (do not round). b) Find the mean and standard deviation. Use the formulas or calculator. Explain calculator steps. c) If a student must study at least 2 hours to pass the test, what is the probability of passing?