1. If $w$ is an imaginary root of the equation $x^{3}=1$, then the product $\left(1-w+w^{2}\right)\left(1+w-w^{2}\right)$ equals ( )
A. 4
B. $w$
C. 2
D. $w^{2}$
1. A $\left(1+\omega-\omega^{2}\right)\left(1-\omega+\omega^{2}\right)=(2+2 \omega)(-2 \omega)=4$