1. One question ask "Which statement below regarding the First Law of Thermodynamics is best? Select the correct answer." One of the wrong answer is "A system can do work externally only if its internal energy decreases. " What does it mean do work externally? 2. Another question ask "Which of the following statements is true? Select the correct answer." One of the wrong answer is "You only need to know the amount of thermal energy a body contains to calculate its temperature. " How to correct this sentence? 3. For definition STP, the tempature is 273.15k, but what is the pressure in the unit of pa and atm?