Why Aeroplane windows are round?

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

John was a very careless driver, so his owner Jacob gave him an offer that he will get an incentive of Rs.30 for every bottle box he delivered without breaking it and he will be charged Rs.90 for every bottle box he broke. Jacob gave John 100 bottles-box to deliver. After delivery, Jacob paid John Rs.2400. How many bottles-box did John break?

I start and end with 500 and carry a 5 in my heart. But I require the first letter and the first number to be complete. I am the name of a King.

Who am I ?

Solve the mathematical equation in the picture below.

The product of three consecutive numbers is 7980.
Then the sum of these consecutive numbers would be?

How many triangles can you find in this given picture?

A rain drop fell from one leaf to another leaf and lost 1/4th of its volume. It then fell to another leaf and lost 1/5th of the volume. It again fell on another leaf and lost 1/5th of the volume.



This process kept repeating till it fell on the last leaf losing 1/75th of its volume.



Can you calculate the total percentage of loss from the initial volume when the drop has fallen to the last leaf accurate up to two decimal places?

Find the hidden panda in the image below.

I speak without a mouth, and hear without ears. I have no-body, but I come alive with the wind. What am I?