What is the fastest way to double your money?

A sundial has the fewest moving parts of any timepiece. Which has the most?

Three people are in a room. Ronni looks at the Nile. The Nile looks at Senthil. Ronni is married but Senthil is not married. At any point, is a married person looking at an unmarried person? Yes, No or Cannot be determined.

You have to fill the below given grid in a manner that every row and column contains the digits 1 to 6. Also, make sure that the squares that are connected with each other must contains the same digit.

I don't get anymore wetter, no matter how much rain falls on me.

Find the next number in the series?
2, 12, 36, 80, 150, 252, 392, _ ?

Find the combined weight of the Cat, Dog and Rabbit in the given picture.

Can you think of any three-dimensional shape that comprises of exactly two surfaces?

The barber of Town shaves all men living in the town. No man living in the town is allowed to shave himself. The barber lives in that town. Who then shaves the barber of the town?

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.