You deposit $150 in a savings account that earns simple interest at a rate of 5.5% per year. how much interest will you have earned after 4 years?
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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.