Can somebody help me out with the question

Which expression calculates the speed in meters per second of an object that travels a distance of 100 m every 20 seconds

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?

Solve each quadratic equation by factoring and using the zero product property. n^2 - 49 = 0