Problem on projection of gravitational force down an inclined plane

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A block rests on an inclined plane of angle $\theta$, as shown. Gravity provides a force $\bfF = (0, -m g)$ on the block.
(a) What is the component of $\bfF$ in the downhill direction?
(b) What is the projection of $\bfF$ in the same direction?

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