When 508,000,000 is written in scientific notation, what will be the value of the decimal number? pi help

Ineed with this problem 21 show steps

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?

If its non of them tell me..valerie took a day-trip. she drove from her house for a while and took a coffee break. after her coffee break, she continued driving. after  2  hours of driving after her coffee break, her distance from her house was  210  miles. her average speed during the whole trip was  60  miles per hour.valerie created the equation  y−210=60(x−2)  to represent this situation, where  xx  represents the time in hours from her coffee break and  yy  represents the distance in miles from her house.which graph correctly represents valerie's distance from her house after her coffee break?