How many automobile licence plates can be made if the inscription on each contains two different letters followed by three different digits ?

How many different car licence plates can be constructed, if the licences contain three letters of the English alphabet followed by a three digit number, if repetition are allowed?

How many signals can be made by hoisting 5 flags of different colours ?

How many planes can be made to pass through three distinct points?

How many different necklaces can be formed with 6 white and 5 red beads ?

How many selections of 4 books can be made from 8 different-books ?

In how many ways can 5 different books be tied up in three bundles?

In how many ways can 18 different books be divided equally among three students ?

Can two different equipotential surfaces intersect each other?

How many permutations can be made out of the letters of the word 'TRIANGLE ' ?