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What is the simplified form of (3.25x10^3)(7.8x10^6) written in scientific notation?

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.

Shannon drove for 540 minutes. if she traveled 65 miles per hour,how many total miles did she travel?