1. Who invented Bleaching Powder ?

Answer: Tennant of Britain in 1798

2. Who invented Refrigerator ?

Answer:

Oliver Evans in 1805

3. Who invented Helicopter ?

Answer:

Igor Sikorsky

4. Who invented Aeroplane

Answer: Orville & Wilbur Wright in 1903

5. Who invented Radar ?

Answer:

Sir Robert Watson-Watt

6. Who invented Printing Press ?

Answer:

Johannes Gutenberg

7. Who invented Steam Engine (Condenser)

Answer: James Watt of Britain in 1765