To measure the interaction force between a basketball and the backboard, we attached a force plate to the backboard. When a 898 $$\rm{g}$$ basketball hit the force plate with a speed of 15 $$\rm{m/s}$$, a graph of force of the plate on the ball versus time ($$\rm{ms}$$) was recorded as shown in the figure.

## Part 1#

What was the rebound speed of the ball from the plate? [Hint: since the force is in the $$+x$$-direction, the ball must be thrown in the $$-x$$-direction.]

Please enter in a numeric value in $$\rm{m/s}$$.