A 12.0 kg shell is launched at an angle of 30.0* above the horizontal with an initial speed of 100 m/s. At its highest point, the shell explodes into two fragments, one three times heavier than the other. The two fragments reach the ground at the same time. Ignore air resistance. If the heavier fragment lands back at the point from which the shell was launched, what is the horizontal speed, [ Select ] of the lighter fragment? How much energy, { Select ] was released in the explosion