Always in you, Sometimes on you;

If I surround you, I can kill you.

What am I?

A swan sits at the center of a perfectly circular lake. At an edge of the lake stands a ravenous monster waiting to devour the swan. The monster can not enter the water, but it will run around the circumference of the lake to try to catch the swan as soon as it reaches the shore. The monster moves at 4 times the speed of the swan, and it will always move in the direction along the shore that brings it closer to the swan the quickest. Both the swan and the the monster can change directions in an instant.
The swan knows that if it can reach the lake's shore without the monster right on top of it, it can instantly escape into the surrounding forest.

How can the swan successfully escape?

I am a word of 12 alphabets.

* Alphabets 12, 4, 7, 2, 5 : Eastern beast of burden
* Alphabets 1, 8, 10, 9 are street made famous by Sinclair Lewis.
* Alphabets 11, 3, 6 are past.

On whole it means a person suffering from delusions of greatness.

What Is it ?

How is a fly different from a mosquito?

A mile-long train is moving at sixty miles an hour when it reaches a mile-long tunnel. How long does it take the entire train to pass through the tunnel?

Count the Triangle in the figure given below:

Cristina was born in 1888. She just had her 30th birthday today how did that happen?

There are two candles. Both will only burn exactly for an hour. How will you use these two candles to measure forty-five minutes?

Rahul decided to meet Simran so he boards a local train from Bombay station. Just after the station, there is a 1km long tunnel. The train starts and is now accelerating. Rahul is a claustrophobic guy, so what is the best position for him to sit?

By using 'because' continuously three times, can you make an English statement ?