Let $\vec{F}=\alpha x \vec{i}+b y \vec{j}+c z \vec{k}$ Where A, B and C Are Constants

Let $\vec{F}=\alpha x \vec{i}+b y \vec{j}+c z \vec{k}$ where a, b and c are constants.Suppose that the flux of $\vec { F }$ through a surface of area 3 lying in the plane y = 3, oriented in the positive y-direction, is 45.Find the flux of $\vec { F}$ through a surface of area 4 lying in the plane y = 3, oriented in the negative y-direction.