What does this below rebus puzzle mean?

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

Take 9 from 6, 10 from 9, 50 from 40, and leave 6.

How Come ??

One absent-minded ancient philosopher forgot to wind up his only clock in the house. He had no radio, TV, telephone, internet, or any other means for telling time. So he travelled on foot to his friend's place a few miles down the straight desert road. He stayed at his friend's house for the night and when he came back home, he knew how to set his clock. How did he know?

Why is the Hole below a Lock?

What two things can you never eat for breakfast?

There is a square of a particular number which when doubled, becomes 7 more than its quarter.

Can you find the number?

1 + 9 + 8 = ?
considering, 28 + 8 + 92 = 10

Give it food and it will live; give it water and it will die.

While going to your grandmother's house, you counted Twenty houses on the right side. While returning back to your home, you counted Twenty houses on the left side.

How many houses are there between your home and your grandmother's home?