Can y'all me with this problem and i don't get it at alll

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

Which choice names the hypotenuse of triangle xyz? a. segment yx b. segment yz c. segment ab d. segment zx

Martha is training for a duathlon, which includes biking and running. she knows that yesterday she covered a total distance of over 55.5 miles in more than than 4.5 hours of training. martha runs at a speed of 6 mph and bikes at a rate of 15.5 mph.