Which equations show the associative property?
select each correct answer.
(a)(−8 1/1+(−1 5/6))+(−5 1/6)=(−5 1/6)+(−8 1/1+(−1 5/6))

(b)2 1/6+(−1/6+(−3 7/8))=(2 1/6+(−1/6))+(−3 7/8)

(c)(1/4+(−4/5))+(3/5)=1/4+(−4/5+3/5

) (d)2 1/2 +(-2/3+(-4 1/9))=2 1/2 –(2/3+4 1/9

Standard deviation of 19,29,21,22,23

Find the value of x. give reasons to justify your solutions! c ∈ ae

1. according to the internal revenue service, the mean tax refund for the year 2007 was $2,708. assume the standard deviation is $650 and that the amounts refunded follow a normal probability distribution. a. what percent of the refunds are more than $3,000? b. what percent of the refunds are more than $3,000 but less than $4,000? c. what percent of the refunds are less than $2,000?