\rbqquest{
$(1+i)^4 = {}$
}

\rbqchoice{
\begin{enumerate}[a)]
\item $-1$
\item $4$
\item $-4$
\item $-\sqrt{2}$
\item $4i$
\item None of the above
\end{enumerate}
}

\rbqans{
\begin{tabular}{cccc}
&Modulus&Argument&$a+bi$\\
\hline
\\
$(1+i)^0$&1&0&1\\
$(1+i)^1$&$\sqrt{2}$&$\pi/4$&$1+i$\\
$(1+i)^2$&$2$&$\pi/2$&$2i$\\
$(1+i)^3$&$2\sqrt{2}$&$3\pi/4$&$-2+2i$\\
$(1+i)^4$&$4$&$2\pi=0$&$-4$
\end{tabular}
\smallskip\\
These powers all lie on a spiral emanating from the origin.  


The answer is (c); thus $(1+i)$ is a fourth root of $-4$.
}
