A 14kg projectile is launched at 380m/s at a 55 (degrees) angle to the horizontal. At the peak of its trajectory it collides with a second projectile moving horizontally, in the opposite direction, at 140m/s . The two stick together and land 9.8km horizontally downrange from the first projectile's launch point. Find the mass of the second projectile. Express your answer using two significant figures in kg.