Which expression would be easier to simplify if you used the associative property to change the grouping? O A. (27 + 4.5 +1.5 O B. ( 3/2+ 5/2) +(-7/3) O C. -1/2 + [(-5/3) +(-3) O D. 14+ (20+80)

Express the following as a function of a single angle, cos(60) cos(-20) - sin(60) sin(-20)

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?

When 142 is added to a number the result is 64 more then 3 times the number. option 35 37 39 41