Please everything that I put on this app no one has answered I’m just wasting points now

You are at a restaurant and owe $38 for your meal. you want to leave a 20% tip. how much will your tip be?

In the sixth grade 13 out of 20 students have a dog if there are 152 sixth grade students how many of them have a dog

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?