A 7000 kg truck travelling at 18.6 m/s, loses it brakes and collides with the rear end of a smaller car in front of it which has a mass of 3000 kg and is travelling in the same direction at 18.5 m/s. If the speed of the front car is increased to 19.82 m/s as a result of the collision, what is the speed of the rear car after the collision?

The flame produced by the burner of a gas (propane) grill is a pale blue color when enough air mixes with the propane (c3h8) to burn it completely. for every gram of propane that flows through the burner, what volume of air is needed to burn it completely? assume that the temperature of the burner is 195.0°c, the pressure is 1.05 atm, and the mole fraction of o2 in air is 0.210.