If R2=.68, b0=15, b1=30 and b2=-50 in a multiple regression with two explanatory variables (X1 and X2) and both explanatory variables are significant and the ANOVA p-value is 0.03, answer the following question: If the units on Y are dollars and the units on X1 are hours, how many more dollars are predicted when the value of X1 increases by 3 hours, holding the value of X2 constant