Please answer the questions below with workings!! (4,5 &6)

Asphere has a diameter of 10 in. what is the volume of the sphere?

Sarah took the advertising department from her company on a round trip to meet with a potential client. including sarah a total of 11 people took the trip. she was able to purchase coach tickets for $280 and first class tickets for $1280. she used her total budget for airfare for the trip, which was $6080. how many first class tickets did she buy? how many coach tickets did she buy?

What does the sign of the slope tell you about a line?