Please help, I need to study for a math test on Thursday, but I'm stuck on this question. Please do your best at answering and include an explanation. I will give brainliest to whoever includes an explanation. Thanks!!! ☺️ ☺️ ☺️ ☺️

Which graph represents an even function?

Awater truck is filling a swimming pool. the equation that represents this relationship is y=19.75x where y is the number of gallons of water in the pool and x is the number of minutes the truck has been filling the pool.

Using pert, adam munson was able to determine that the expected project completion time for the construction of a pleasure yacht is 21 months, and the project variance is 4. a) what is the probability that the project will be completed in 17 months? b) what is the probability that the project will be completed in 20 months? c) what is the probability that the project will be completed in 23 months? d) what is the probability that the project will be completed in 25 months? e) what is the due date that yields a 95% chance of completion?