Mario's Plumbing charges a $50 fee, plus $65 per hour of labor. Luigi's Plumbing represents their charges with the following function: f(x) = 75x + 30.
What is the difference in the companies' flat fees (y-intercepts)?

A. $10
B. $20
C. $25
D. $35

Carlos spent 1 1/4 hours doing his math homework he spent 1/4 of his time practicing his multiplication facts how many hours to carlos been practicing his multiplication facts

Me with this assignment ! i only partially understand, so explain. also it's a work sample. at the championship bike race, steve and paula were fighting for first place. steve was 175 feet ahead of paula and had only 300 feet left to go. he was very tired and was going only 9 feet per second. paula was desperate to catch up and was going 15 feet per second. who won the bike race and by how far did she/he win?

You work in a hospital that has 9 floors. you need to see 3 patients on each floor. how many patients do you need to see in all?