Consider the Interaction Model $E ( y ) = 7 + 3 x _ { 1 } - 4 x _ { 2 } + 5 x _ { 1 } x _ { 2 }$

Multiple Choice

Consider the interaction model $E ( y ) = 7 + 3 x _ { 1 } - 4 x _ { 2 } + 5 x _ { 1 } x _ { 2 }$ . Find the slope of the line relating $E ( y$ and $x _ { 1 }$ when $x _ { 2 } = 2$ .

A) 1
B) 10
C) 16
D) 13