Question 1192767
A baseball is thrown upward from a building 20 m high with a velocity of 15 m/sec. Its distance from the ground after t seconds is modeled by the function f(t)=-4.9t^2+15t+20. When will the ball hit the ground? Round your answer to the nearest tenth.
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When f(t)=-4.9t^2+15t+20 = 0.