Can you convert the number zero(0) into a positive number using just one mathematical operator ?

Who has married many women but was never married?

When I get multiplied by any number, the sum of the figures in the product is always me. What am I?

Our product and our sum always give the same answer. Who are we?

Where do fish keep their money?

I have cities, but no houses. I have mountains, but no trees. I have water, but no fish. What am I?

Which number should replace the question mark?

There were two grandmothers and their two granddaughters.
There were two husbands and their two wives.
There were two fathers and their two daughters.
There were two mothers and their two sons.
There were two maidens and their two mothers.
There were two sisters and their two brothers.
Yet there are only six, who are buried here,
All are born legitimate and relationships clear.
How can this happen?

Prove that twice of ten is the same as twice of eleven.

There are seven sisters in a house in a village where there is no electricity or any gadget.

Sister-1: Reading Novel
Sister-2: Cooking
Sister-3: Playing Chess
Sister-4: Playing Sudoku
Sister-5: Washing clothes
Sister-6: Gardening

what is Sister-7 doing ?