A ball is thrown from an initial height of 3 feet with an initial upward velocity of 28 ft / s. The ball's height
h (in feet) after t seconds is given by the following.
h = 3+28t-16t^2. Find all values of t for which the ball's height is 11 feet.
Round your answer(s) to the nearest hundredth.
(If there is more than one answer, use the "or" button.)