In functions, each x value has its own corresponding y value, this meaning that the x value cannot repeat, and if it does it is not considered a function
Looking at the graph, no x value repeat, thus the graph represents a function
Im not sure but 1.25 equals 1 1/4 and 16 cups equal a gallon.
16 divided by 1.25 is 12 which means that 12 of those ten servings equal a gallon. 10 times 12 is 120 which becomes ur answer. Once again im not sure but i hope that ive helped.