Manny is repairing a window air conditioning unit on the 11th floor of a building and is approximately 98 feet off the ground. While working, Manny drops his screwdriver. The height h of the screwdriver in feet after t seconds of falling from the 11th floor is modeled by the function h = −16t^2 + 98. How long will it take for the screwdriver to reach the ground? Show your work below and round to the nearest tenth if necessary.