Which is one of the conditions for constructing a difference in two proportions confidence interval? O n1and n2 must both be at least 30.
O All expected frequencies are at least five.
O nip1210,nı (1-P1) z 10, and n2 P2210, n2 (1-p_2) 2 10.
O Your correlation coefficient must be close to 1 or -1.

Abank gives 6.5% interest per year. what is the growth factor b in this situation?

Describe the 2 algebraic methods you can use to find the zeros of the function f(t)=-16t^2+400.

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?