Questions

Infrared radiation

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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.

Capitalism is an economic system followed by a country or a society which is characterized by Privately owned businesses, a market economy and profits.

Capitalism is defined as "production for exchange" driven by the desire for personal accumulation of money receipts in such exchanges, mediated by free markets. The markets themselves are driven by the needs and wants of consumers and those of society as a whole in the form of the bourgeois state.

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

Cytoplasm does not contains all the organelles.

Yes, the given statement that water is more dense than cooking oil is TRUE as water more denser than oil it is sinked when it is poured in oil.