Can anyone tell me a word in the English dictionary which has a silent 'z'?

Solve the riddle below:

If a Chicken says, 'All chickens are liars" is the chicken telling the truth?

There is a hypothetical state between the USA and Mexico border 'Tango'.
Here 70 percent of the population have defective eyesight, 75 percent are hard of hearing, 80 percent have Nose trouble and 85 percent suffer from allergies, what percentage (at a minimum) suffer from all four ailments?

John and Jenni are a married couple. They have two kids, one of them is a girl. Assume safely that the probability of each gender is 1/2.
What is the probability that the other kid is also a girl?

Hint: It is not 1/2 as you would first think.

Can it be possible to build a house that has all its four walls facing towards the South?

A shepherd had 18 sheep, out of which, all but ten died.

Can you tell us how many sheep was he left with?

There was a blind man. He had four socks in his drawer either black or white. He opened it and took out two socks. Now the probability that it was a pair of white socks is 1/2.

Can you find out the probability that he had taken out a pair of black socks ?

By removing one matchstick and adding one matchstick, can you convert the word "ZOO" to an animal name?

A large container is kept in open under the rain. Every passing hour, the water collected inside the container becomes double what it was.

In ten hours, the container is filled completely. Can you calculate how long would it have taken to be filled in half?

Why 1729 is a magic number? Answer Logically.