What four weights can be used to balance from 1 to 30 pounds?

In a jungle where there are no street lights or any other artificial source of lights, I notice a black snake crossing the road.
How did I get sight of the snake?

Make the seating arrangement of 10 children in such a way that there are 5 rows with 4 children in each row.

John was piloting a plane behind a car but was never able to overtake it. Why?

Different lights make me strange by changing me into different sizes. What am I?

If you remove one from eleven, it becomes ten. If you remove one from nine, it becomes ten.

How is this possible?

Can you count the number of blocks in the picture below?

They do not possess flesh or feathers or scales or bone
But still, they are blessed with fingers and thumbs of their own.

Two guards were guarding the camp.Guard-1 was looking towards the south to make sure no threat is coming from the road.Guard-2 was looking at the north to make sure no threat is coming from the top. Suddenly Guard-1 ask the Guard-2 why he is smiling?How Guard-1 knows that Guard-2 is smiling?

The measurement of time, That can't be found on a clock, But can be looked upon on a map.

Who is He ?