What does this rebus mean?

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Move three sticks of the spiral below to form a square.

Many have heard it, but nobody has ever seen it, and it will not speak back until spoken to. What is it?

He loves to dance, twist and prance, he shakes his tail, and as a way he sails, wingless he flies into the sky. What is he?

Identify the 10 differences between the two given pictures.

I look at you, you look at me, I raise my right, you raise your left. What am I?

In Greek mythology, the Sphinx sat outside of Thebes and asked this riddle of all travellers who passed by. If the traveller failed to solve the riddle, then the Sphinx killed him/her. And if the traveller answered the riddle correctly, then the Sphinx would destroy herself. The riddle:

What goes on four legs in the morning, on two legs at noon, and on three legs in the evening?

Oedipus solved the riddle, and the Sphinx destroyed herself.

I hide my treasure in the ground, my tail is big and fluffy. If you spot me in a tree, please don’t call me scruffy. What am I?

Which number should replace the question mark?

A man dies of old age on his 25 birthday. How is this possible?