How many words can a pen with half refill write?

A seven-year-old kid challenged his classmates that he can make the number one disappear by adding something to it.

How can he do that?

Which is faster, Heat or Cold ? Explain.

I am first found in caves, now prolific online; I am a depiction, a drawing, a symbol, or sign. I will convey whichever mood you could wish; or for that matter, a fist, flask, or fish. What am I?

In the image below, you can see two glasses and two matchsticks.You need to move four matchsticks in such a manner that the crosses come inside the glasses. Note: you cannot move the crossed.

There is a brick of gold and a brick of iron in a boat (both 10-inch blocks), if they are both dropped into the water which will make the water level higher?

Can you guess the name of the month by looking the below rebus ?

Can you name some countries which do not have the alphabet 'A' in them?

What Time Should the last watch show in the below figure?

The day after tomorrow will be three days before Tuesday. Can you find out what is today?