A block is being pressed against a vertical wall with external force F→ and sliding down (as shown in the figure). When it slides down for a distance of d, what is the expression for the work done by the external force F→ during the process? Pick the correct answer Fdcos(γ) Fdsin(γ) Fdcos(β) Fdsin(α) Fdcos(α) The work done by the external force on the block is: Pick the correct answer Positive Cannot determine Zero Negative