I REALLY need help :( The table shows the outputs, y, for different inputs, x:

Input (x) 1 2 3 4

Output (y) 5 5 7 9

Part A: Do the data in this table represent a function? Justify your answer. (3 points)

Part B: Compare the data in the table with the relation f(x) = 2x − 8. Which relation has a greater value when x = 4? (2 points)

Part C: Using the relation in Part B, what is the value of x if f(x) = 34? (5 points)

I know Part A is a yes but I got 0 for part B which I'm not even sure if its correct. Even if it IS 0 I don't know how that would work for part C.