Can you make four (4) nines (9) equal 100?

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?

John was writing his first book. After saving the document, he locked his laptop with a password and mentioned some phrases for the hint box.

A friend of his tried opening his laptop but found out that it was password protected. Following is the hint that appeared.
1 mobile 3 books 2 roars 1 night 4 balls 2 lighters 1 ghost 1 hat 3 watches.

Can you help him in cracking the password?

Always in you, Sometimes on you;

If I surround you, I can kill you.

What am I?

What is the difference between a jeweller and a jailer?

The square root of number 121 is "11". What is the square root of the number "12345678987654321."?

Four men were in a boat on the lake. The boat turns over, and all four men sink to the bottom of the lake, yet not a single man got wet! Why?

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

An old Woman left INR 33,333 to be divided equally among two fathers and two sons and each was to receive INR 11,111.
How was this possible?

Spot what is wrong here in below Picture?