Can someone please help everything's in the picture.

Answer:
(a) Each input has only 1 output, making it a function.
(b) If any of the inputs had multiple outputs, it would not be a function. For example, if Input: 4 Output: 9 was on the table, it would no longer be a function since there is already a different output value for 4.
(c) y = 2x - 1... This equation works since 2(3) - 1 = 5, 2(4) - 1 = 7, 2(6) - 1 = 12, and 2(11) - 1 = 22