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Active Calculus - Multivariable

Activity 9.3.7.
Let \(\vu = \langle 2, 6 \rangle\text{.}\)
(a)
Let \(\vv = \langle 4, -8 \rangle\text{.}\) Find \(\proj_{\vv} \vu\text{,}\) \(\comp_{\vv} \vu\text{,}\) and \(\proj_{\perp \vv} \vu\text{.}\) Draw a picture to illustrate the vectors involved. Finally, express \(\vu\) as the sum of two vectors where one is parallel to \(\vv\) and the other is perpendicular to \(\vv\text{.}\)
(b)
Now let \(\vw = \langle -2,4 \rangle \text{.}\) Add \(\vw\) to the picture you drew in the previous part. Without doing any calculations, find \(\proj_{\vw} \vu\text{.}\) Explain your reasoning.
(c)
Find a vector \(\vw\) not parallel to \(\vz = \langle 3,4 \rangle \) such that \(\proj_{\vz} \vw\) has length \(10\text{.}\) Note that there are infinitely many different answers!