Can anyone pls Help me in dis pls

This stem-and-leaf plot represents the heights of the students on ralph's basketball team. one student's height is missing from the plot. if the mean height of all the students on the team is 61 inches, what is the missing height? a. 55 in. b. 59 in. c. 61 in. d. 65 in.

Which of the following circles have their centers in the third quadrant? check all that apply.

I’m really confused and need to learn this