A certain street contains 100 buildings. They are numbered from 1 to 100. How many 9's are used in these numbers?

Always in you, Sometimes on you;

If I surround you, I can kill you.

What am I?

How many triangles are there in the picture below?

In the formation, you can see a few arranged matchsticks. Can you form three squares by moving just three matchsticks?

Here is a mathematical expression that also secretly tells a movie name. What movie is that?

Different lights make me strange by changing me into different sizes. What am I?

Irene killed hundreds of people mercilessly and yet the police were not able to put her behind the bars. Why?

How can you make a TV, a bed, a dog, and a car liquid?

A Car is crossing a bridge 2 miles long. The bridge can only hold 10000 lbs, which is the exact weight of the car. The Car makes it half way across the bridge and stops. A bird lands on the car. Does the bridge collapse? Explain.

There are three boxes which are labeled as Rs100, Rs150, and Rs200. One box contains two notes of Rs. 50. The second box contains one note of Rs50 and one note of Rs100 The third box contains two Rs. 100 notes. All boxes are labeled incorrectly.

What is the minimum number of boxes you must check in order to label all boxes correctly?