At a farm, four employees harvest 48 pounds of food over a certain number of hours. Each employee works the number of hours shown. (the hours for the employees are) Employee A: 6 hours
Employee B: 4 hours
Employee C: 6
Employee D: 8 hours

Complex numbers multiply √-4 * √-25 and show all intermediate steps. alternative notation is sqrt(-4) * sqrt(-25).

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.

Which equation represents h for right triangle abc