The following model was fitted to a sample of 25 students using data obtained at the end of their freshman year in college. The aim was to explain students' weight gains:
$$
y=\beta_0+\beta_1 x_1+\beta_2 x_2+\beta_3 x_3+\varepsilon
$$
where
$y=$ weight gained, in pounds, during freshman year
$x_1=$ average number of meals eaten per week
$x_2=$ average number of hours of exercise per week
$x_3=$ average number of beers consumed per week
The least squares estimates of the regression parameters were as follows:
$$
b_0=7.35 \quad b_1=0.653 \quad b_2=-1.345 \quad b_3=0.613
$$
Predict the weight gain for a freshman who eats an average of 20 meals per week, exercises an average of 10 hours per week, and consumes an average of 6 beers per week.