Plsss!! Which of the following equations is balanced?

Question 3 options:

1) 2H2 + O2 → 4H2O

2) 4Na + O2 → 2Na2O

3) Fe2O3 + H2 → 2Fe + 3H2O

4) CH4 + O2 → CO2 + H2O

Which real-world scenarios below represent physical and chemical changes? -running a car -exploding fireworks -mixing water and powdered drink mix -combining oil and vinegar to make salad dressing -taking aspirin for a headache -diluting bleach with water-digesting dinner-spreading peanut butter on bread

Arollercoaster car at the top of a hill has potential energy kinetic energy chemical energy light energy

Can someone me with 6 to 10 plz this is for masteries test.