What is full of holes but still holds water?

What will be the best approach to finding all the prime numbers less than 75 that leave an odd reminder when we divide them with 5?

I make two people out of one. What am I?

Find the smallest sentence with all the English alphabet.

A man died, leaving $10,000,000 for his widow, 5 sons and 4 daughters. Each daughter received an equal amount, each son received twice as much as a daughter, and the widow received three times as much as a son.

How much did the widow receive?

How will you measure 15 minutes using two hourglasses of 7 minutes and 11 minutes respectively?

A worker is to perform work for you for seven straight days. In return for his work, you will pay him 1/7th of a bar of gold per day. The worker requires a daily payment of 1/7th of the bar of gold. What and where are the fewest number of cuts to the bar of gold that will allow you to pay him 1/7th each day?

John is looking at Jenifer, but Jenifer is looking at Jacob. John is married, but Jacob is not.

Is a married person looking at an unmarried person ?

What is the riddle which can be asked all day with a different correct answer each time.

You have four chains. Each chain has three links in it. Although it is difficult to cut the links, you wish to make a single loop with all 12 links. What is the fewest number of cuts you must make to accomplish this task?