Answer:
true, false, true, false
Explanation:
On a graph, you can see wether or not you have a function by doing the VLT, or vertical line test. Hold a pen or pencil vertically on the paper on move it from left to right. If no 2 points touch the pencil at once, it's a function.
Another way to find out is if any two different points have the same x coordinate. If there is a match, this is not a function. For example, 3,4 and 3,9 cause the graph to not be a function.