It's for my math class and an extra boost will be so great

We just started the introduction into circles and i have no idea how to do this.

Given the graphed function below which of the following orders pairs are found on the inverse 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.