If 5 cats catch 5 mice in 5 minutes, how long will it take one cat to catch a mouse?

Known by all without exception, Forever here, for your protection, Sometimes strong, sometimes weak, Right after the night I come - hot and chic. And while millions of miles away, I always get to you, I find my way. No life around could do without me, Can you guess what I might be?

If there are fifteen crows on a fence and the farmer shoots a third of them, how many crows are left?

There are 2 people near the river and both of them want to get on the other side. The boat can only take one of them. But they got across.
How?

What has one letter and starts with an E?

What mathematical symbol can be put between 5 and 9, to get a number bigger than 5 and smaller than 9?

You have to put a letter on the following to make it a meaningful word. The only challenge is that you can't use 'E'.

S E Q U E N C _

You board a train. The train will have to enter a tunnel soon. You are claustrophobic. Which place is the best for you to sit?

What does an Island and the letter T have in common?

What numbers should go on the bottom line?
3 6 9 15
8 2 10 12
11 8 19 27
19 10 29 39
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