For acceleration, we have: A = (V^2 - Vo^2)/2(X) --> A = [(0)^2 - (-10)^2]/2(25) = -100/50 = -2.00 m/s^2. Just ignore the negative sign, it just means that the elevator is moving downward. For the tension, we have 3 forces acting on the elevator, the Tension and the Force pointing upward and the Weight pointing downward. So we write: T + - F + (-W) = 0 --> W - F = T --> (800 kg)(9.81 m/s^2) + (800 kg)(2 m/s^2) = T --> 9448 N = T.