This is the concept of graphs and volume of the solid figures, given that the triangle J,K,L was rotated along the x-axis, the resultant figure was cone with with radius of 5 units and a height of 4 units; The volume of a cone is given by; V=πr^2(h/3) r=5 units h=4 units V=π*5^2*(4/3) V=104.72 units^3 the answer is B]