\textbf{97-} \textbf{Which of the following questions is the one the passage is primarily written to answer?}\\
\hspace*{1em} 1) How was Mar formed?\\
\hspace*{1em} 2) What life forms can Mars support?\\
\hspace*{1em} 3) What does the Planet Mars look like?\\
\hspace*{1em} 4) How big is Mars compared to other planets in the solar system?