Estimate each sum using front end estimation and then rounding 75 + 22

The diagonals of a rhombus are 12 inch and 16 inch long, the length of a side of a rhombus is 10 inch, what is the height of the rhombus

Which representation has a constant of variation of -2.5

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?