200.0 mL of a 0.600 M solution of KCl is diluted to 600.0 mL. What is the new concentration of the solution?

Which of the following statements is true? a. most heat energy is easily recovered and used for useful actions. b. friction causes molecules to vibrate more slowly. burning air and gasoline in an c. engine changes chemical energy into mechanical energy. it is impossible to d. change mechanical energy into mechanical energy.