a total of 6000 is invested: part 8% and the remainder at 12%. how much is invested at each rate if the annual interest is 540

Simplify (a/b - b/a) times (a - a^2/a+b) a - a^2/a=b is a mixed number

1. there are 25 students who started computer programming in elementary school and 25 students who started computer programming in middle school. the first group had a mean final project grade of 95% and the second group had a mean final project grade of 92%. the line plot shows the differences after 10 rerandomizations. determine whether the difference in the means of the two groups is significant based on the line plot. explain your answer.

Satchi found a used bookstore that sells pre-owned dvds and cds. dvds cost $9 each, and cds cost $7 each. satchi can spend no more than $45.