Two Heads

Question: You come to a cross road and see a man with two heads. A sign tells you that one head always tells the truth and the other one always lies. The sign also tells you that one road leads to life and posterity while the other leads to certain death. Now the hard part. You can only ask ONE head ONE question. What do you ask? Which road do you take? Hint: One head knows what the other will tell you.

Question: People see through me, but none pass through without killing me. I can be anywhere, and can be seen double or single. What am I?

Question: What can be broken but never forgotten?

Question: Which thing that comes once in a year, twice in a week?

Question: You are trying to get your chicken, fox, and wheat to the barn. However, the barn is on the other side of the river. You are on a boat and can only transport one animal or wheat at a time. You must choose carefully not to leave the wrong two together, though. It's either the fox will eat the chicken or the chicken will eat the wheat. How do you take each thing across safely?

Question: During what month do people sleep the least?