A=4, b=2,c=-1 find value of a-b+c

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?

The measurement of one angle of a right triangle is 42° what is the measurement of the third angle? (there is no picture)

Me i'm timed ! a. -2 to 1 b. -1.5 to 0.5c. 0 to 1d. 0.5 to 1.5