Danielle earns a 7.25% commission on everything she sells at the electronics store where she works. She also earns a base salary of $625 per week. How much did she earn last week if she sold $4,500 in electronics merchandise? Round your intermediate calculations and answer to the nearest cent

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?