Kidnapper

Question: The Duke of Riddleton has been kidnapped. The police have identified 3 suspects, all of which had motive, and opportunity to do the deed. Their names are Andrew, Jason, and Shawn. All of them claim that they didn't do it, but Jason and Shawn seemed nervous wile being questioned. There was a note left behind, with the following description: 1491011. Who kidnapped the duke?

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?

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Question: Leap Year is every 4 years. True or False ?

Question: When is 99 more than 100?

Question: What can be broken but never forgotten?