25.
answer is B since it is adding he amount of the bill with the amount of the tip.
the other 3 will all calculate just the amount of the tip
26
3x-4 needs to equal or be below 8
rearrange the formula to 3x,=8+4
so 3x<=12
12/3 = 4
so x <= 4 to satisfy the inequality
so answer is A