1. Let's say that the armor is 10 cm thick (or however thick it is). Since the bullet is capable of shooting through anything, when the bullet hits the armor it will penetrate 5 cm of that armor. The bullet still gets through half of the armor (true), and does not penetrate the armor at all (true).
2. Yes he can. But whether he dies or not is another problem.
3. No. There's no point in accepting a mission that is bound to fail from the start.
4. I agree with the previous posts. Go to the time when the girl was already born, and there should be no problem at all.
5. "Twice as cold" is rather subjective. Instead of measuring the temperature, maybe we can try this: if today I wear a coat, maybe tomorrow I should wear two coats.
6. "Yes" is false, "No" will confuse the asker.
7. I will travel together with the light from my headlights.
8. "God has the power to create anything. He also has the power to lift anything. Can he create something that he cannot lift?" this is a very nice paradox. If he is a God, then he is (supposed to be) able to create anything. He is also (supposed to be) capable of lifting anything. But if he is to create a stone that is supposed to be unliftable, yet he is capable of lifting it; that would neglect the fact that he can create anything out of his will.