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Acid rain is caused due to pollution of the atmosphere by:

Marble is a metamorphic rock of:

Which type of wave does not require a medium for propagation?

On a clean glass plate, a drop of water spreads to form a thin layer whereas a drop of mercury remains almost spherical because:

The time period of a pendulum when taken to the Moon would:

Plants absorb dissolved nitrates from soil and convert them into

Which of the following substances is classified as a carbohydrate?

Metallurgy is the process of:

Who proposed the 'Law of Octaves' in the periodic classification of elements?

Water is a good solvent of ionic salts because -