Answer:
11. This is a function because every input, the number of hours studied, has one output, the grade.
12. Looking at the graph it already has a point for 2 hours. Plotting another 2 hour point would no longer make it a function. This is because there are now two outputs for one input.
Step-by-step explanation:
A function is a relation from a set of inputs to a set of possible outputs where each input is related to exactly one output.