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?

I am written with two letters.
I said with the one.
I usually am seen with the two.

Who am I?

A time long back, there lived a king who ruled the great kingdom of Trojan House. As a part of the renovation of the kingdom to meet future security needs, he asked his chief architect to lay down a new play in a manner that all of his 10 castles are connected through five straight walls and each wall must connect four castles together. He also asked the architect that at least one of his castles should be protected with walls. The architect could not come up with any solution that served all of King's choices, but he suggested the best plan that you can see in the picture below. Can you find a better solution to serve the king's demand?

I’m tall when I’m young, and I’m short when I’m old. What am I?

Look at the below sequence of letters and tell us what the next letter should be:

O T T F F S S ?

Identify the 10 differences between the two given pictures.

Solve the mathematical equation in the picture below.

It walks on 4 when its young, walks on 2 when it's older, and walks on 3 when its very old?

I have Rs.50 and I spend it in the way as below.

When monkey rotate the gear, which mark will be hit 1 or 2 ?