Hi I would appreciate any help I can get with these questions

1. What is the internal energy of an ideal gas at O K (absolute zero) A. Zero B. negative C. Positive 2. When an ideal gas confined in a piston does work on the surroundings under isothermal conditions, which of the following statements are true about the properties of the gas? (a) the internal energy decreases and the enthalpy increases (b) the internal energy increases and the enthalpy increases (c) the internal energy and the enthalpy both decrease (d) the internal energy and the enthalpy both increase (e) the internal energy remains the same, but the enthalpy changes (f) both internal energy and enthalpy remain the same 2. Reversible work is always than irreversible work and a reversible process is usually than an irreversible process (Fill in the two blanks, the two answers are separated by a semicolon in the options below) (a) equal to; faster (b) less or equal to; slower (c) more or equal to; faster (d) equal to; slower (e) less or equal to; faster (f) more or equal to; slower 4. The human body can be best approximated as: An open adiabatic system An open isothermal system A closed isolated system A closed isothermal system A closed adiabatic system W909\"? 5. Calculate the change in internal energy in the following systems: a. An electric motor produces 15 kJ of energy every second as mechanical work, and also loses 2 kJ to the surroundings as heat. b. When a spring is wound, 100] of work is done on it, but at the same time, 15 J escaped to the surroundings as heat. 6. A sample containing 2 moles of Helium is expanded isothermally at O0 C from 5 dm3 to ZOdm3 (i) reversibly (ii) against a constant external pressure equal to the final pressure of the gas and (iii) freely (against zero external pressure). For each of the three processes, calculate: q, w, and AU