What does this below rebus puzzle mean?

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

In the given picture, you can find two letters missing. When two particular letters are placed in the missing spots, you get an eight-letter word while reading in the anti-clockwise direction. Can you find out the missing letters and the missing word eventually?

As you can see that fifteen matches have been used to form an arrangement. What you have to do is remove any six of them to make them ten.

The captain of a ship was telling this interesting story: "We travelled the sea far and wide. At one time, two of my sailors were standing on opposite sides of the ship. One was looking west and the other one east. And at the same time, they could see each other clearly." How can that be possible?

Buy me, smell me or deliver me, I do not change.

Who am I?

Which English verb becomes past tense just by rearranging the letters?

Here is a conversation between a couple who both are software professionals.

Husband: Hey! What is your date of birth?
Wife Replied Angrily: It is 591062400
Husband after doing some calculations replied, "Got It".

What is the DOB of the wife?

What came first, the chicken or the egg?

Using eight eights and addition only, can you make 1000?