What are the variables in the expression x+8-y?

The speed of a falling object increases at a constant rate as time increases since the object was dropped. which graph could represent the relationship betweent time in seconds, and s, speed in meters per second? speed of a falling object object over time

Measures of the angle of r, 31 s (x+4) t (3x+9)

According to the data set, where should the upper quartile line of the box plot be placed?