The sides of a triangle have lengths 11,15, and k, where k is an integer. For how many values of k is the triangle obtuse?<spanclass=′latex−bold′>(A)</span>5<spanclass=′latex−bold′>(B)</span>7<spanclass=′latex−bold′>(C)</span>12<spanclass=′latex−bold′>(D)</span>13<spanclass=′latex−bold′>(E)</span>14