As determined by the graph, f(-9) = 9
ANSWER

EXPLANATION
The average velocity of the ball is the rateof displacement over the total time.
The height of the ball, in feet, after t seconds is given by the function:

At time t=1, the height of the ball is


At time t=6, the height of the ball is



The average velocity




You don't have the answer choices but if there were no decomposers within an ecosystem, some plants could die due to a shortage of nutrients
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