Which word does the below Plexor means ?

Which wheel of car does not rotate when you turn your car right?

When it is alive we sing, when it is dead we clap our hands. What is it?

A seven-year-old kid challenged his classmates that he can make the number one disappear by adding something to it.

How can he do that?

I have no doors but I have keys, I have no rooms but I have space, you can enter but you can’t leave! What am I?

An exterior architect is asked by a builder to plant seven trees in a manner that there are exactly six rows of trees in a straight line and each row has three trees in particular.

How will he do it?

You have four chains. Each chain has three links in it. Although it is difficult to cut the links, you wish to make a single loop with all 12 links. What is the fewest number of cuts you must make to accomplish this task?

In a school, there are four subjects. Seventy percent of students study English, seventy five percent of students study Science, eighty five percent of students study Mathematics and eighty percent of students study Spanish.

Can you calculate the percentage of students that study all four subjects?

I know a 5-digit number having a property that With a 1 after it, it is three times as large as it would be with a one before it.

Guess the number?

Replace the question mark with the correct number below.