a) The time it takes for a group of students to complete a Computer quiz is normally distributed with a mean of 1 hour and a standard deviation of 12 minutes. i) If a student is selected at random, what is the probability that the time to complete the quiz is at least 75 minutes? (3 marks) ii) Find the probability that the time to complete the quiz is between 50 minutes to 70 minutes. (3 marks) iii) If 65% of the students spend more than t minutes to complete the quiz, determine the value of t. (4 marks)