this whole thing hurts my brain.

Answer:
1.) C. 32
2.) Stem-and-leaf plot
Step-by-step explanation:
This is a stem-and-leaf plot. The stem represents tens and the leaves represent units. To make it easier to look at, it is equivalent to this:
Now, to find the mean, add up all the numbers and divide the sum by the number of values.
(20 + 28 + 29 + 29 + 31 + 32 + 36 + 41 + 42)/9 = 288/9 = 32