6. Find the volume of the solid region R bounded by: z-r-y+4, z=0, y=0, x=0, x=4 (Show the steps.) 7. Set up the double integral to evaluate the integrall f(x,y)dA . when f(x, y) - x+ y, and the region R is :rectangle with vertices (0.0), (0.7), (5.7), (5.0)