Write but do not evaluate an expression involving a dx dy or dy dx double integral that could be used to find the average value of the function f(x,y) = y/(x³ to y³) over the triangle bound.
a) ∬f(x,y)dxdy = ___
b) ∬f(x,y)dydx = ___
c) ∬f(x,y)dxdy = ___
d) ∬f(x,y)dydx = ___