How many triangles are there on the puzzle below?

I possess a head

I flaunt a tail

But I don't have mouth or legs

Can you find out who I am?

When it is alive we sing, when it is dead we clap our hands. What is it?

There was once a college that offered a class on probability applied to the real world. The class was relatively easy, but there was a catch. There were no homework assignments or tests, but there was a final exam that would have only one question on it. When everyone received the test paper it was a blank sheet of paper with a solitary question on it: 'What is the risk?'.Most students were able to pass, but only one student received 100% for the class! Even stranger was that he only wrote down one word!
What did he write?

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

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

Can you solve this amazing hard number series problem?
7, 8, 10, 12, 16, 18 ?

Which letter of the alphabet has the most water?

Why is it very easy to weigh a fish?

One absent-minded ancient philosopher forgot to wind up his only clock in the house. He had no radio, TV, telephone, internet, or any other means for telling time. So he travelled on foot to his friend's place a few miles down the straight desert road. He stayed at his friend's house for the night and when he came back home, he knew how to set his clock. How did he know?