I am a type of room you cannot enter or leave. Raised from the ground below, I could be poisonous or a delicious treat. What am I?

You have $100 with you and you have to buy 100 balls with it. 100 is the exact figure and you can't go below or above the numbers and you have to use the entire $100. If there is no kind of tax applied how many of each of the following balls will you be able to buy:

Green Balls costing $6
Yellow Balls costing $3
Black Balls costing $0.10

Now, how many of each must you buy to fulfil the condition given?

Two boys wish to cross a river. The only way to get to the other side is by boat, but that boat can only take one boy at a time. The boat cannot return on its own, there are no ropes or similar tricks, yet both boys manage to cross using the boat.

How?

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

You need to arrange three 7 and mathematical symbols to form number 1?

Can you find out the missing number in the grid?

Spot 5 differences in two Christmas tree below:

John was driving a bus and got stuck when passing through an underpass. Then came Jacob with a needle and got the bus out of the underpass.

What did the boy do?

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

In this image, you can see three almost identical Doraemon images. Can you spot the odd one out from them?