plz solve step by step correctly

Question 2 Consider the two following data sets X and Y, Data set X 4 5 3 3 7 1 8 5 Data set Y 5 19 7 7 7 12 7 11 Some useful summations are provided below, Et = 36, _y: - 65, _= = 198, E Ty: = 279. a) Find an expression for the line of regression in the following form, y = a + br. [6 marks] b) Use your regression equation to predict the value of y when x = 15. [2 marks] c) Comment on the reliability of your prediction. Justify your answer fully. [Your answer to this part of the question must be typed.] [2 marks]