Why Aeroplane windows are round?

Prove that the below maths equation is true.

8 + 8 = 91

Decode this picture on T-Shirt and tell what it says ?

Christina has four daughters, and each of her daughters has a brother. How many children does Christina have?

What word begins and ends with an E, but has only one letter?

You have an empty wine bottle with a cork that has been secured at the top in a normal way. There is a metal ring inside the bottle that is suspended by a string.

How can you make the metal ring drop to the bottom if you are not allowed to touch anything - not the bottle, not the cork, not the thread and not the ring?

I am beautiful, up in the sky. I am magical, yet I cannot fly. To people I bring luck, and to some people, riches. The boy at my end does whatever he wishes. What am I?

How much will a 38° angle measure when looked at under a microscope that magnifies ten times?

Solve the puzzle by telling what does below picture means.

What does this rebus mean?

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