Answer:
1) Function 2) Function 3) Not a function 4) Not a function
Step-by-step explanation:
Performing the Vertical line test, we can draw a vertical line. If this drawn line hits the graph only once, then we can consider it a function. In other words, the vertical line says that there is only one output value y for a unique one input value for x. An essential condition for a relation to be a function.
