Good Riddles

Question: Farrah left her key under the mat and when she came back she lost it.The painter said he painted the wall ,the security said she didn't know, annd the janitor said he cleaned the floor. Who took the key?

Question: Find the five digit number in which the first digit is one half of the the 4 fourth digit, the second digit is one fourth of the last digit, the fourth digit is 3 times the second digit, and the third digit is the first digit plus 4.

Question: I can be shared by many or spread to few, I am as fragile as silk yet as strong as steel. Wars have been fought in my name, generations defined by me. What am I?

Question: I can be seen and heard miles away, only show my position for a couple of seconds, but if touched it can kill you instantly.

Question: What looks like a duck but is red?