The lowest region of the earth’s atmosphere comes between the earth and stratosphere. what is this region’s name?

What is the addictive drug in tobacco ______________?

A. Ethanol
B. Nicotine
C. Ammonia
D. Tar

A. Nephoscope
B. Stethoscope
C. Metroscope
D. None of the above

Which element is used as moderator in nuclear reactor?

A. Light water
B. Dense water
C. Fresh water
D. Heavy water

A. 80
B. 200
C. 120
D. None

A. Because the sunlight falling on it is scattered.
B. Because the sunlight falling on it is absorbed.
C. Because the sunlight falling on it is refracted.
D. Because the sunlight falling on it is reflected.

“The ocean looks blue because red, orange and yellow (long wavelength light) are absorbed more strongly by water than is blue (short wavelength light). So when white light from the sun enters the ocean, it is mostly the blue that gets returned. Same reason the sky is blue.”

A. fission
B. fusion
C. thermal combustion
D. combined effect of all the above three