PLEASE HELP ME PLEASE

Which of the following is a function? a.) {(-2, -4/5), (-1,-,,-1)} b.) {(-2,,1/,3/,1)} c.) {(-22)} d.) {(-21)}

What is the slope of the line? a. -5/2 b.2/5 c. 5/2 d.7/2

Me : julio wears a blue shirt every 3 days. larry wears a blue shirt every 4 days. on april 11, both julio and larry wore a blue shirt. what is the next date that they will both wear a blue shirt?