Help me with my math please ASAP

Which expression is equivalent to? assume x > 0 and y > 0.

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.

The domain of the following relation: r: {(3, 5), (8, 6), (2, 1), (8, 6)} is (1 point) no domain exists {1, 5, 6} {3, 8, 2, 8} {2, 3, 8}