If the relationships below are given in the form (input, output), which pairing always describes a function?
(number of doors in a car, number of cup holders in the car)
(height of a building in feet, height of the building in inches)
(beverage charge on a bill, total meal charge on the bill)
(distance from home during a trip, time elapsed during the trip)

Trent wants to buy 2 packs of trading cards for 3 dollars each. the trading card packs that trent normally buys tend to come in packs of 6, 10, 12, or 15 cards. after selecting 2 packs, trent found that the first pack of cards cost 25 cents per card, and the second pack cost 30 cents per card. trent uses this information to write the equations below in order to compare c, the number of cards in each pack.

In priyas math class there are 10 boys and 15 girls. what is the ratio of boys to girls in priyas math class? express your answer as a decimal

What is the inverse of f(x) = 6x -24