D Desert Organisms Must Cope with Extreme and Variable Conditions

D Desert organisms must cope with extreme and variable conditions. Their coping strategies frequently involve retreating to a sub-surface refuge. Researchers in New Mexico, investigating the underground shelter choices by Gila Monsters (Heloderma suspectum), hypothesized that depth might be a factor. They reasoned that deeper shelters would be less susceptible to extremes of heat and cold and thus depth would be preferred in a shelter. Depth data for 20 chosen shelters and 20 available shelters not chosen are presented in the table at right.

$\begin{array}{l}\text { Shelter Depths (cm) }\\\begin{array} { | c | c | c | c | } \hline \text { Chosen } & \text { Nearest } & \text { Chosen } & \text { Nearest } \\\hline 94 & 54 & 33 & 32 \\\hline 89 & 6 & 15 & 14 \\\hline 32 & 57 & 27 & 7 \\\hline 76 & 50 & 27 & 32 \\\hline 65 & 46 & 85 & 28 \\\hline 30 & 41 & 52 & 52 \\\hline 68 & 43 & 80 & 50 \\\hline 84 & 59 & 33 & 55 \\\hline 10 & 55 & 79 & 69 \\\hline 58 & 53 & 71 & 55 \\\hline\end{array}\end{array}$
a) Display these data using a comparative (back-to-back) stem-and-leaf plot. Use the
stems shown below, and be sure to include all information needed to compare the
two distributions.
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(b) Describe the similarities and differences between the chosen and not chosen
shelter depths.
(c) Are these data consistent with the researchers' expectations? Explain, using
specific aspect(s) of your plot in part (a).