Can you find the key in the picture below?

In the image given, you can find several triangles. Can you count them all?

Out of the nine cats that you can see in the picture, there are only two that are completely identical. Can you find them out?

In the picture given below, can you find out which digit will take place of the question mark?

Can you tell a 3D object that has just two surfaces?

When does a USA Potato change its nationality?

A wife and her husband were driving in their car on the highway. All of a sudden, they ran out of gas. So the husband said to the wife, 'Now, you stay here. I will go down the highway to the nearest gas station, and it will be about 1 hour. Just listen to the radio and read some books, and remember to lock all the windows and doors. I will leave the keys with you.' So, off the husband went, and the wife first locked ALL the windows and doors. Next, she turned on the radio, and this is what she heard on the news report:
'THERE IS A MURDERER ON THE LOOSE. HE WAS LAST SEEN ON THE HIGHWAY, WEARING ALL BLACK, ABOUT 5 FOOT 11 INCHES. PLEASE, BE AWARE AND CONTACT THE POLICE IMMEDIATELY.' The wife got very scared. She turned off the radio and double-checked the locked doors. Then she saw the murderer, only a couple of feet away from the car. An hour later, the husband returned to his car. Inside the car, his wife was DEAD, she had been murdered. All the windows were still locked, and the doors. No windows were broken, and the car was in PERFECT condition. No scratches or anything, it was the same way as when he left it. How did the murderer kill the wife?

A man has a barrel filled with oil that weighs 100 pounds, and then he puts something into it. Now the barrel weighs less than 100 pounds. What did he put in the barrel?

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?

Manish and Manoj play 5 games of chess.
Both Manish and Manoj win the exact same number of games. There is no tie at all.

How?