Questions

Calculation of molar mass of HNO3:

Atomic masses of H, N, O are 1, 14, 16 respectively

Now the molar mass of HNO3 is

HNO3 = 1X1 + 1X14 + 3X16

= 1 + 14 + 48

= 63 g/mol or amu.

Kohinoor diamond was produced from one of the mines in Golconda.

Radio waves have much longer wavelengths and lower frequencies than do visible light waves. In contrast, X-rays have much shorter wavelengths and higher frequencies. 

Ultraviolet Light (UV). part of the electromagnetic spectrum that consists of waves with frequencies higher than those of visible light and lower than those of x-rays.

Sad means being unhappy, sorrowful, mournful, wistful,...

Hence, Somber means cheerless i.e, unhappy which is synonym of sad. All other options are opposites of Sad.

A : B = (800 × 8+ 900+ 1000+ 1100+ 1200): (1600 × 8+ 1700+ 1800+ 1900+ 2000)
A : B = 53 : 101
Profit of A ⇒ 7700 ×53/154 = 2650 Rs.

Tips

It would be wise to save this question for the interviewing manager, and not for a peer/technical discussion. Nobody likes a kiss-up, but letting management know that you will communicate openly and honestly with them, always scores big points. The last part of the question can be a good barometer about how easy it will be to become a top performer. You can follow up with a discussion of how you have been successful in your previous jobs.