Introduce notation and write an expression to calculate the average productivity of the agri-cultural land in merced county as a double integral. specify the definition of the function tobe integrated and the domain over which it must be integrated. (you do not need to providea formula of the typef(x, y) =x2+y, rather just explain what the functions and variableswould stand for). 2. using iterated integrals, evaluate the volume above the triangle with vortices (0,0), (2, 1) and (3,0) (in the ry-plane) and below the surface z = 2xy. 3. sketch the region of integration and evaluate the iterated integral sl cos(2")dx dy jo j 1/3