How do you know if a graph, table, or mapping diagram is a function?

Rosy waxes 2/3 of her car with 1/4 bottle of car wax. at this rate, what fraction of the bottle of car wax will rosey use to wax her entire car

Seattle, washington is known for being rainy. one day last month, 8 inches of rain fell in 1 1/2 hours. what us the rate of the rainfall expressed in ft per plzzz write a proportion i will give you 100 points

Jonathan can type 20 documents in 40 minutes ,and susan can type it in 30 minutes and jack can type it in 24 minutes working together ,how much time will it is take them type the same document