The maximum possible height of the arch is

Question

A political party orders an arch for the entrance to the ground in which the annual convention is being held. The profile of the arch follows the equation y = 2x-0.1x² where y is the height of the arch in meters. The maximum possible height of the arch is                                                                                                                                          

      (a) 8 meters                                                         (b) 10 meters

      (c) 12 meters                                                       (d) 14 meters