Why do we preferably have round manhole covers and not square ones?

What is the word or phrase?

On her drawing table, Sayna lit 12 coloured candles. A few seconds later she blew two candles off.

How many candles Sayna have at the end?

When is the top of a mountain similar to a savings account?

Open a Laptop which is password protected. Hint for the password is given as below:

1 mobile 3 books 2 Boards 1 night 4 balls 2 lighters 1 ghost 1 hat 3 watches

The average age of 10 members of a committee is the same as it was 4 years ago, because an old member has been replaced by a young member. Find how much younger is the new member ?

Can you name any English verb that becomes its past tense by simply rearranging the alphabets ?

A woman lives in a skyscraper thirty-six floors high and is served by several elevators which stop at each floor going up and down. Each morning she leaves her apartment and goes to one of the elevators. Whichever one she takes is three times more likely to be going up than down. Why?

A pond had 60 fish, out of which, all but 20 died.
How many fishes are now present in that pond?

Count the Triangle in the figure given below: