The data below are the final exams score of eight randomly selected history students and the numbers of hours the slept the night before the exams

Hours of sleep	3	5	2	8	2	4	6	3	5
Exams score	65	80	60	88	66	78	90	99	97

A researcher wishes to predict exams score based on the numbers of hours

a) for this study, what is the response variable? Find the equation of the least square regression line

b) according to the regression model, what is the percentage of the variation in the variable scores that can be predicted using hours in the model

c) what is the value of the correlation coefficient

d) should the model be used to predict the score when the number of hours is 12/ explain