Which three-digit number, made of consecutive digits, like 567, is 2 less than a cube and 2 more than a square?

I came first on earth but second on the heaven.
I also came twice in a week but found just once in a year.
I stay away from months but you can find me in February.

What am I?

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?

How many triangles can you find in this given picture?

In particular commonwealth games, a female participant won silver and gold medals for a single event.

How can this be possible?

Place the numbers from 1 to 9 in the circles in a manner that each side of the triangle sums up to 17.

A crime was committed at baker street. Ibrahim Dakota who was shot in the stomach was the main suspect. Sherlock questioned the suspect. The conversation started as:
Sherlock: What's your story, Ibrahim?
Ibrahim: I was walking around baker street and suddenly a man from the back shot me. I ran as fast as I could to save my life".
Sherlock: That is enough (and ask the police to arrest him).

Why does Sherlock think he is the murderer?

Spot 5 differences in two Christmas tree below:

1 rabbit saw 9 elephants while going to the river. Every elephant saw 3 monkeys going toward the river. Each monkey had 1 parrot in each hand. How many animals are going towards the river?

Can you place six X (crosses) in below board without making three in a row in any way ?