QUESTION $8$

The average value of the function $f(x,y)=xy$ on the triangular region with vertices $(0,0),(1,0)$ and $(1,2)$ is equal to

$$ a$.4$

b$.\frac{1}{2}$

c$.\frac{1}{4}$

d$.\frac{3}{2}$

e$.\frac{2}{5}$