Taussig corp.'s bonds currently sell for $1020. they have a 6.5% annual coupon rate and a 10year maturity. what rate of return should an investor expect to earn if he or she purchases these bonds?

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.