1. The author of 'A Foreign Policy For India' is L.K Advani. 2. 'Wings of Fire' is a book written by A.P.J Abdul kalaam. 3. 'Open' is an Autobiography of Andre Agassi.
You have to actually count all the balls in the pyramid. Simple way is to count the balls in each level.
So lower most level lets say 1st level has 4 x 4 balls; i.e. 16 balls Similarly 2nd level has 3 x 3 balls; i.e. 9 balls. 3rd level has 2 x 2 balls; i.e. 4 balls. The top most level has just 1 ball.