Based on the nebular theory, which of these is a step in the formation of the center of a new planetary system? a) evaporation of condensed gases due to heat b) combination of condensed gases due to gravity c) contraction of condensed gases due to nuclear fission d) expansion of condensed gases due to nuclear fission .

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.