When a relation is drawn on an xy-plane, what is another name for the set of all x-values from its graph

Sunday: 1 1 2 monday: 1 tuesday: 2 1 2 wednesday: 1 3 4 thursday: 2 friday: 1 1 2 saturday: 2 jenna is a swimmer and trains every day. the schedule shown outlines the number of hours she trains each day. what is the total number of hours that jenna trains during the week?

Which of these tables represents a non-linear function?

How do you create a data set with 8 points in it that has a mean of approximately 10 and a standard deviation of approximately 1?