please help me solve this question as soon as possible, thanks a lot.

(a) The amount of time that QUT students devote to their study per week is normally distributed, with a mean of 50 hours and a standard deviation of 5 hours. What is the probability that the mean amount of studying per week for 4 randomly selected QUT students is less than 52 hours? (Round to two decimal places.) (2 marks) (13) At the time of issue of 6.00% coupon bonds. the effective interest rate was 5.50%. The bonds were most liker issued at (par, discount, or a premium). {1 mark)