Midline school takes 255 students to the zoo each ticket cost 9.50 the school received 20% off after 100 tickets how much did the school pay in total for the zoo

please please can some one help me step by step correctly please I would rally appreciated I will also give you five stars and I will thank you

2people are trying different phones to see which one has the better talk time. chatlong has an average of 18 hours with a standard deviation of 2 hours and talk-a-lot has an average of 20 hours with a standard deviation of 3. the two people who tested their phones both got 20 hours of use on their phones. for the z-scores i got 1 for the chatlong company and 0 for talk-a-lot. what is the percentile for each z-score?