The diagram labels x as the distance along the incline from point B to point C. It also asks for "the height of the box at point B". Calculate both the height at B (hB) and the distance x from B to C.

Let's continue with the remaining parts of the problem.

c) Calculate the value of $x$, the height of the box at point B?

The phrasing of this question is ambiguous. The diagram labels $x$ as the distance along the incline from point B to point C. It also asks for "the height of the box at point B". We will calculate both the height at B ($h_B$) and the distance $x$ from B to C.

To solve this problem, we need to use the Work-Energy Theorem, which states that the total work done by non-conservative forces ($W_{nc}$) equals the change in mechanical energy ($\Delta E$).

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