Plz me with the work on the picture i need to give it in tommorow i don't know how to do it ; -;

Ijust need these 2 questions answered (the second pic is just confirmation i'm not confident in that answer)

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.

How is this equation completed? i cannot find any examples in the book.