\documentclass[a4paper]{article}

\usepackage{probsoln}
%uncomment the following line to display the answers
\showanswers

% The following will generate a different set of
% problems in subsequent years
\PSNrandseed{\year}

\begin{document}
\title{Sample Problem Sheet}
\author{Nicola Talbot}
\maketitle

\begin{enumerate}
% Differentiation from first principles
\selectrandomly{1stprncp}{1}

\item Differentiate the following functions:
\begin{enumerate}
\selectrandomly{easy}{5}
\end{enumerate}

% Implicit differentiation
\selectrandomly{implicit}{2}

% Multiple choice question
\selectrandomly{mchoice}{1}

% select one essay style question that doesn't come with a solution

\selectrandomly{nosoln}{1}
\end{enumerate}
\end{document}
