Using the composite trapezoidal rul and simpson's 1/3 rule to solve a double integral

The integral is from -2 to 2 (outside) and 0 to 4 (inside) of

x^2 -3y^2 +xy^3 dx dy

I need to solve it with the composite trapezoidal rule with n=2, and again using a single application of simpson's 1/3 rule. I also need to determine the true percent relative error for each.