Why do we preferably have round manhole covers and not square ones?

This is a classy optical illusion puzzle. What more you can find except bricks in the image below?

I got a bee but no honey.
got an eye but am still blind.
got a sea but no water.
got a tea but no coffee.
got a why but no answer.

What Am I?

There is a barrel with no lid and some wine in it. 'This barrel of wine is more than half full,' said Curly. 'No it's not,' says Mo. 'It's less than half full.' Without any measuring implements and without removing any wine from the barrel, how can they easily determine who is correct?

The product of three consecutive numbers is 7980.
Then the sum of these consecutive numbers would be?

Keyboard words are not in alphabetical order, Why?

If it took eight men ten hours to build a wall, how long would it take four men to build it?

Can you find a seven digit number which describes itself. The first digit is the number of zeros in the number. The second digit is the number of ones in the number, etc. For example, in the number 21200, there are 2 zeros, 1 one, 2 twos, 0 threes and 0 fours.

How can you write nineteen in a manner that if we take out one, it becomes twenty?

A 3 digit number is such that it's unit digit is equal to the product of the other two digits which are prime. Also, the difference between it's reverse and itself is 396.

What is the sum of the three digits?