Two hours after Amanda started her sail boat trip, her friend Kathy decided to join her. Amanda was traveling 8 km/h and Kathy, in her motorboat was traveling 16 km/h. How long did Kathy travel before she caught up to Amanda?

The length of the line segment joining the midpoints of sides ab and bc of the parallelogram abcd is 10. find the length of diagnol ac

Over which interval is the graph of f(x) = x2 + 5x + 6 increasing?

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.