How many liters of salt solution would be needed to provide 40.0 grams of salt if the concentration of the solution is 46.0 g/L? Don't forget your units.

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.