Plz giv explanation as well as answer

A block of stone, with a mass of 3600 kg, is being carried on a light sledge. It is held at rest on a smooth ramp by workers pulling on a rope attached to the block, The ramp makes an angle of 15" with the horizontal, and the rope is parallel to the ramp. Each worker can pull with a force of maximum magnitude 450 N. 3600 kg Figure 3 Diagram of a block of stone carried on a sled, held at rest on an incline a. Draw a force diagram of the situation described b. Calculate the tension in the rope, giving your answer to two significant figures c. Find the minimum number of workers needed to hold the block. d. When modelling forces, it is necessary to make assumptions in order to make the calculation simpler, State and justify any two significant modelling assumptions you have applied in your assessment of the problem in parts (D) and (c)