4 & 5 plz

im stuck on this quiz

1foot = 12 inches; 1 yard = 3 feet

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?

[15 points, algebra 2]simplify the complex fraction and find the restrictions.