I am looking for a word that change both gender and number when i add the letter 'S'.

What Word am I Looking For ?

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

There is a box full of marbles,
all but two are blue,
all but two are green,
and all but two are red.

How many marbles are in the box?

Solve the mathematical equation in the picture below.

I am not alive, but I grow; I don't have lungs, but I need air; I don't have a mouth, but water kills me. What am I?

Which flower has two lips?

Replace the question mark with the number below given a simple math problem.

Which tank will fill first?

There are three boxes. One is labeled "APPLES" another is labeled "ORANGES". The last one is labeled "APPLES AND ORANGES". You know that each is labeled incorrectly. You may ask me to pick one fruit from one box which you choose.

How can you label the boxes correctly?

A bag contains 64 balls of eight different colours. There are eight of each colour (including red). What is the least number you would have to pick, without looking, to be sure of selecting 3 red balls?