Fill in the missing space with the correct figure.

The unit of momentum is

Pipes A and C can fill an empty cistern in 32 and 48 hrs, respectively while Pipe B can drain the filled cistern in 24hrs. If the three pipes are turned on together when the cistern is empty, how many hrs will it take for the cistern to be 2/3 full?

What is the mean of first hundred natural numbers?

A/an ___ flame is produced when the oxygen supply is sufficient.

Select the number missing from the given series.

3, 12, ___, 21612

Which celebrity is the author of the book 'An Unsuitable Boy'?

In the modern periodic table, which of the two periods contain 8 elements each?