A box with mass $m$ moves down a slope of length $l$ and vertical height $d$ while opposing a frictional force $F$. As the box travels down the slope, it loses gravitational potential energy and does work against friction. Which row gives the decrease in gravitational potential energy and the work done against friction?
- Aloss $= mgd$, work $= Fl$
- Bloss $= mgd$, work $= Fd$
- Closs $= mgl$, work $= Fl$
- Dloss $= mgl$, work $= Fd$