A ball is thrown from an initial height of 3 feet with an initial upward velocity of 30 ft / s. The ball's height 
 h (in feet) after t seconds is given by the following. 
 h = 3+30t-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.)