You pull a block along the ice, as shown below. Which of these could be the net force equations in the x and y directions? Use the convention that N is the normal force, f is the frictional force, Fg is the force of gravity, and Fapp is the force you apply. F 250 OFx = Fapp Cos 250 - f = ma Fy = N - Fapp sin 25 - F, = ma OF2 = Fapp - f = ma CFy = N - Fg = 0 O EFF = Fapp sin 25 - f = ma E Fy = N + Fapp Cos 250 - Fg = 0 O E Fx = Fapp Cos 25 - f = ma E Fy = N + Fapp sin 250 - F, = 0