It Has Been Hypothesized That Overall Academic Success for Freshmen

It has been hypothesized that overall academic success for freshmen at college as measured by
Grade point average (GPA) is a function of IQ scores (X1) , hours spent studying each week (X2) , and
One's high school average (X3) . Suppose the regression equation is:
Y' = -6.9 + 0.055X1 + 0.107X2 + 0.0083X3.
The multiple standard error is 6.313 and R2 = 0.826.Assuming other independent variables are held
Constant, what effect on the GPA will there be if the numbers of hours spent studying per week
Increases from 32 to 36?

A) 3.1446
B) -0.824
C) +0.428
D) -0.428
E) +0.824