Indicate which property is illustrated in step 1.

step 1 5 + (3 + 10) + 0 = 5 + (10 + 3) + 0
step 2 = (5 + 10) + (3 + 0)
step 3 = (5 + 10) + 3
step 4 = 15 + 3
a associative property of multiplication
b commutative property of addition
c identity property of addition
d associative property of addition

What value of x is in the solution set of –5x – 15 > 10 + 20x?

Acylinder has volume 45π and radius 3. what is it’s height?

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?