please explain this

A study looked at the relationship between time spent writing an essay and grade received in 45 first year psychology students. Descriptive data are summarized below for essay mark (essay) and hours spent preparing (hours) as well as the correlation between the two. X essay = 63.45 Sessay = 6.757 X hours = 8.349 Shours = 2.725 TEH = 0.267 a) Compute the regression parameters, indicating what each represents. b) What is the estimated minimum hours spent preparing to obtain 90% on the essay? c) What is the error in estimation for the predicted values? Interpret this value. d) What is the variance accounted for in essay mark from hours preparing? e) Is the slope coefficient of hours predicting essay mark statistically significant