Answer
$ŷ=3.313~mm$
Work Step by Step
$ŷ=7.790-0.382x_1-0.587x_2-0.925x_3+0.091x_2x_3$
- Age: 8 years old, that is, $x_1=8$
- Male: $x_2=1$
- From Chizé: $x_3=1$
$ŷ=7.790-0.382\times8-0.587\times1-0.925\times1+0.091\times1\times1=3.313$