Help plz help help plz

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

Richard save $32 in march he saved $48 in april and $38 in may then richard spent $113 on a keyboard how much money does richard have left

Which of the following values in the set below will make the equation 5x + 6 = 6 true? (only input the number.) {0, 1, 2, 3, 4}