Question 31
Homoeography was invented by ?
Question 32
Helicopter was invented by ?
Question 33
DDT was invented by ?
Question 34
Pneumatic tyre was invented by ?
Question 35
Elias Home invented ?
Question 36
Stethoscope was invented by ?
Question 37
Bushwell invented ?
Question 38
Analytical Engine was invented by ?
Question 39
Who discovered oxygen?
Question 40
Inert gases were discovered by?