How to do subexercises or exercise parts with the xsim package?

Question

I quite often see, and myself create, exercises which consist of multiple subexercises or parts, like this:

# Exercise 1
Two cars are traveling in opposite directions. 
They are 2.7km apart, driving 50km/h and 65km/h, respectively.
a) Write the equations of motion for the two cars.
b) Find the time t at which the two cars will meet.
c) Find the distance traveled by the cars when they meet.

As far as I can see, this is not a feature directly provided by the xsim package. Any recommendations on how to achieve this by other means?

A solution with the enumerate or itemize environment works, but maybe there are other ways.

\documentclass{article}
\usepackage{xsim}
\begin{document}
\begin{exercise}
Two cars travel ....
\begin{enumerate}
\item Write the equations ...
\item Find the time ...
\item Find the distance ...
\end{enumerate}
\end{exercise}
\end{document}

If one uses a solution like the above one, one has to keep the subexercises or parts in the same order in both the exercise and solution environment manually.

Answer 1

I'd simply use enumerate or tasks (from the tasks package).

\documentclass{article}
\usepackage{xsim,tasks,siunitx}

\begin{document}

\begin{exercise}[subtitle=Cars]
  Two cars are traveling in opposite directions. They are
  \SI{2.7}{\kilo\meter} apart, driving \SI{50}{\kilo\meter\per\hour} and
  \SI{65}{\kilo\meter\per\hour}, respectively.
  \begin{tasks}(2)
    \task Write the equations of motion for the two cars. (\addpoints{1})
    \task Find the time $t$ at which the two cars will meet. (\addpoints{2})
    \task Find the distance traveled by the cars when they
      meet. (\addpoints{2})
  \end{tasks}
\end{exercise}

\end{document}

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Depending on your setup it might also be a possibility to use xsim's environments for the subexercises directly. An example for this can be found here: Randomly selecting subquestions in exsheets.