Which pair of numbers is relatively prime? a. 21 and 39 b. 15 and 27 c. 10 and 21 d. 12 and 54

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?

That table shows measurements (in invhes$ from cubes with different side lengths. which pairs of variables have a linear relationship? check all that apply

Labc is reflected across x = 1 and y = -3. what are the coordinates of the reflection image of a after both reflections?