291. The heaviest naturally-occurring element is_________?
292. The heaviest man made element found so for is__________?
293. Which instrument is used for viewing the sun?
D. None of these
294. ___________ is a strong smelling agent added to LPG cylinders to detect leakage?
A. Nitrogen Peroxide
B. Ethyl Mercaptan
C. Carbon Monoxide
D. Sulphur Dioxide
295. A crescograph is a device for measuring the growth in __________?
A. Micro Organism
296. Which of the following is used in water purification?
A. Reverse Osmosis
D. Turgor Pressure
297. lightest metal is__________?
298. Which of the following pollutants in water causes “Minamata disease?
A. Methyl Mercury
299. The process of converting wet waste to manure is___________?
300. Which of the following organisms releases molecular oxygen into water?