21. Shelly has a cell phone plan that costs $9.99 per month plus $0.05 per minute. Her total bill for the month is $25.59. Write and solve an equation to find how
many minutes she used for the month.

Cody was 165cm tall on the first day of school this year, which was 10% taller than he was on the first day of school last year.

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.

Melissa is purchasing a $160,000 home and her bank is offering her a 30-year mortgage at a 4.9% interest rate. in order to lower her monthly payment, melissa will make a 20% down payment and will purchase 3 points. what will her monthly mortgage payment be? a. $645.98 b. $650.46 c. $662.93 d. $606.69