Why is the Hole below a Lock?

Sherlock Holmes was challenged to make a pre-drawn line smaller without erasing it. He did it in fractions of seconds. How?

All of the flowers I have are orchids except two. All of the flowers I have are hibiscuses except two. All of the flowers I have are roses except two.

Can you tell me how many flowers I have?

Quickly Solve this riddle

7 - 4 + 3 * 0 + 1 = ?

What comes
Once in a Year
Twice in a Month
4 times in a Week
6 times in a Day

What does below chemistry rebus means?

What has no start, end, or centre?

Which of the following words don't belong in the group and why?
CORSET, COSTER, SECTOR, ESCORT, COURTS

The first box has two white balls. The second box has two black balls. The third box has a white and a black ball.

Boxes are labeled but all labels are wrong!

You are allowed to open one box, pick one ball at random, see its colour and put it back into the box, without seeing the colour of the other ball.

How many such operations are necessary to correctly label the boxes?

What does a man do only once in his lifetime, but women do once a year after they are 29?