When two waves are in sync with each other and occupy the same place at the same time, how is the resulting wave determined? by averaging the wavelengths of the two waves by dividing the frequencies of the two waves by multiplying the velocities of the two waves by adding the amplitude of the two waves

Two cannon balls weighing 18 kg and 24 kg are chained together and fired horizontally with a velocity of 165 m/s from the top of a 21-m wall. the chain breaks during the flight of the cannonballs and the 18-kg cannonball strikes the ground at t = 1.5 s, at a distance of 240 m from the foot of the wall, and 7 m to the right of the line of fire. determine the position of the other cannonball at that instant. neglect the resistance of the air.