Rearrange the following six sentences (1), (2), (3), (4), (5) and (6) in the proper sequence to form a meaningful paragraph; then answer the questions given below them.
1. With all this experimentation he incurred an expenditure of over a million dollars before success smiled on him.
2. Edison invented the long lasting electric light bulb.
3. To find a fibre to burn inside a bulb he experimented with over two thousand items.
4. We thus owe the miracle of light as much to his perseverance as to his genius.
5. However he did not invent it overnight.
6. His friends too travelled all over the world from South America to India in search of a suitable fibre.
Which of the following should be the SIXTH (LAST) sentence after rearrangement?