Can someone explain this and help me?

The first five terms of a linear sequence are given below. 7 , 12 , 17, 22 , 27 , what is the next term of the sequence?

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

Me i'm timed right now! a. (0,-5)b. (0,-3)c. (0,3) d. (0,5)