Eisha is making trail mix. the ratio of raisins to granola in the mix is 2 to 5. if eisha adds 4 cups of raisins to her trail mix, how many cups of granola should she add?
a 5 cups c 10 cups
b 7 cups d 20 cups

Use stokes' theorem to evaluate c f · dr where c is oriented counterclockwise as viewed from above. f(x, y, z) = xyi + 5zj + 7yk, c is the curve of intersection of the plane x + z = 8 and the cylinder x2 + y2 = 81.