Why are all black people so quick ?

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

A famous swimmer can swim downstream in a lake in exactly 40 minutes with the lake current.
He can swim upstream in that lake in exactly 60 minutes against the lake current.
The length of the lake is 2 km.

How long he can cover the distance of one side at a still lake with no current?

What makes this number unique: 8,549,176,320?

We know that the number 7 is the prime followed by a cube. Which next number is also a prime followed by a cube?

I have holes on the top and bottom. I have holes on my left and on my right. And I have holes in the middle, yet I still hold water. What am I?

If you drop a 15 kg iron bar and a 5 kg bag of cotton from a height of 50 meters which will reach the ground first?

When does a USA Potato change its nationality?

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

You see a boat filled with people, yet there isn’t a single person on board. How is that possible?