A person pushing a horizontal, uniformly loaded, 27.80 kg wheelbarrow of length L is attempting to get it over a step of height h = 0.390R, where R is the wheel's radius. The center of gravity of the wheelbarrow is in the center of the wheelbarrow. What is the horizontal component Px of the minimum force P→ necessary to push the wheelbarrow over the step? The gravitational acceleration is g = 9.81 m/s2. Px =