Using Only Five 5's and any mathematical operator make sum as 37

In two decks of cards, what is the least amount of cards you must take to be *guaranteed* at least one four-of-a-kind?

The first person saw the bridge step on it and crossed,
the second person saw the bridge did not step on it but crossed,
the third person did not see the bridge did not step on it but crossed.
Who are these people?

There is a number which when you multiply by 3 and subtract 2 from the result, then the resulting number is the reverse of the actual number.

What is the smallest number that stands true on the statement?

There is one thing that goes round the house and also inside the house but never even share a brief touch. What is it?

What can you see in the middle of March and April that you can never see in any other month?

Find the hidden panda in the image below.

Find the value of "a" by solving the maths equation in the picture below:

A King wants to send the diamond ring to his girlfriend securely. He got multiple locks and their corresponding keys. His girlfriend does not have any keys to these locks and if he sends the key without a lock, the key can be copied in the way. How can King send the ring to his girlfriend securely?

A plane crashed between the border of Mexico and America. Where do you bury the survivors?