What is the centre of gravity?

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

I am green and found in the forest and have needles instead of leaves. What am I?
Hint 1: It can be used for Christmas decorations.
Hint 2: I have a strong, scent that is used in air fresheners.

What does does this rebus picture means ?

What is the next number in the series?

15 29 56 108 208 ?

You were playing ping pong with your friend. Suddenly the ball fell into a narrow metal pipe that was imbedded in the concrete surface of the floor one foot deep. Now you don't have any other ball and you desperately want to take it out and play. You and your friend have your shoelaces, your tennis paddle and a plastic water bottle. However, the bottle cannot fit into the pipe.

How will you take the ball out?

How can you tell a raw egg from a hard-boiled egg?

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

Find the next number in the series.
1 10 24 43 67 ?

How do you go from 98 to 720 using just one letter?