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

You have a 12 liters jug full of water. You have two empty 8 liters and 5 liters jug. How can you divide the water into two equal parts using these jugs?

What's a single-digit number with no value?

If I put in one canary per cage, I have one bird too many. If I put in two canaries per cage, I have one cage too many. How many cages and canaries do I have?

Which word is least like the others? Third, fourth, fifth, sixth, seventh, eighth, ninth?

Can anyone tell me a word in the English dictionary which has a silent 'z'?

An ape is trying to climb on a pole that is 60 feet high. Due to the slippery surface, the ape climbs 3 feet in a minute only to slip back 2 feet.

How much time do you think the monkey will take to reach the top of the pole?

Prove that twice of ten is the same as twice of eleven.

The captain of a ship is telling you an interesting story and then poses a question. He says, “I have travelled the oceans far and wide. One time, two of my sailors were standing on opposite sides of the ship. One was looking west and the other one east. And at the same time, they could see each other clearly. Can you tell me how that was possible?”

I have a five and a three-gallon jar. Assuming there is an infinite supply of water, how can I measure one-gallon water?