Answer:
QUESTION 1: (-3,0), (1,1), (5, 2), (9,3)
QUESTION 2: Draw a mapping diagram (see question 3)
QUESTION 3: Yes, the image below is a function.
Explanation:
For question 1, you can pair the domains (x-values) with any y-value. The y-values can repeat.
For question 3b, you must understand that domains cannot repeat, but ranges (y-values can). In 3b, every x-value has a unique y-value which means that it is a function. You can also determine is something is a function by seeing if its graph passes the vertical line test.