Please explain how to do this

Someone answer this asap for gabriella uses the current exchange rate to write the function, h(x), where x is the number of u.s. dollars and h(x) is the number of euros, the european union currency. she checks the rate and finds that h(100) = 7.5. which statement best describes what h(100) = 75 signifies? a. gabriella averages 7.5 u.s. dollars for every 100 euros. b. gabriella averages 100 u.s. dollars for every 25 euros. c. gabriella can exchange 75 u.s. dollars for 100 euros. d. gabriella can exchange 100 u.s. dollars for 75 euros.

What is the slope of the line passing through the points (3, 3) and (5, 7) ? 1. 2 2. 1/2 3. −2 4. −1/2

Huong is organizing paperback and hardback books for her club's used book sale. the number of paperbacks is 12 less than three times the number of hardbacks. huong had 162 paperbacks. how many hardback books were there?