Which of the following is a retirement plan sponsored by an employer that allows employees to set aside money for retirement?
A. IRA
B. 401(k)
C. Roth 401(k)
D. Roth IRA

If cos(2x) = tan^2(y), show that cos(2y) = tan^2(x).

Which spreadsheet would be used to compute the first nine terms of the geometric sequence a^n=32•(1/2)n-1

Set $r$ is a set of rectangles such that (1) only the grid points shown here are used as vertices, (2) all sides are vertical or horizontal and (3) no two rectangles in the set are congruent. if $r$ contains the maximum possible number of rectangles given these conditions, what fraction of the rectangles in set $r$ are squares? express your answer as a common fraction.