Chapter 11.4, Problem 3QCE

Suppose that u, v, and w are vectors in 3-space such that $\text{u}\times \text{v}=〈2,7,3〉\text{ and u}\times \text{w}=〈-5,4,0〉.$

$\begin{array}{l}\left(\text{a}\right)\text{u}\times \text{u}=\text{\_\_\_\_\_}\\ \left(\text{b}\right)\text{v}\times \text{u}=\text{\_\_\_\_\_}\\ \left(\text{c}\right)\text{u}\times \left(\text{v}+\text{w}\right)=\text{\_\_\_\_\_}\\ \left(\text{d}\right)\text{u}\times \left(\text{2w}\right)=\text{\_\_\_\_\_}\end{array}$