The expression below can be used to find the area of a triangle with a base of 4.5 in. and a height of 2.1 in. One-half (n) (2.1) What number should go in place of n to find the area of the triangle?

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.