A block is pushed so that it moves up a ramp at constant speed. B Identify from choices (i)-(iii) below the appropriate description for the work done by the specified force while the block moves from point A to point B. (i) is zero. (ii) is less than zero. (iii) is greater than zero. (a) The work done on the block by the hand. Explain your reasoning. (b) The work done on the block by the normal force from the ramp. Explain your reasoning. (c) The work done on the block by friction. Explain your reasoning. (d) The work done on the block by the gravitational force. Explain your reasoning. (e) The net work done on the block. Explain your reasoning.