Solders are typically made from tin or lead or a combination of both in the ratio of 63 : 377 respectively.

Correct Option: A

Solders are typically made from tin or lead or a combination of both in the ratio of 63 : 377 respectively.

Nature gas is 95 percent Methane (CH₄) Plus four other hydrocarbons:
Ethane (C₂ H₆) - 2.5 %, Propane (C₃ H₈) - 0.2 %, Butane (C₄ H₁₀) - 0.06%, Pentanes Plus (C₅ H₁₂ + C₁₀ H₂₂) -0.02%. It also contains small amounts of: Nitrogen (N₂) - 1.6%, Carbon Dixoide (CO₂) - 0.7%, Hydrogen Sulphide (H₂S) - trace, Water (H₂O) - trace

Correct Option: A

Nature gas is 95 percent Methane (CH₄) Plus four other hydrocarbons:
Ethane (C₂ H₆) - 2.5 %, Propane (C₃ H₈) - 0.2 %, Butane (C₄ H₁₀) - 0.06%, Pentanes Plus (C₅ H₁₂ + C₁₀ H₂₂) -0.02%. It also contains small amounts of: Nitrogen (N₂) - 1.6%, Carbon Dixoide (CO₂) - 0.7%, Hydrogen Sulphide (H₂S) - trace, Water (H₂O) - trace

Pyrethrin is a natural plant derived substance that comes from the chrysanthemum cinerariaefolium.

Correct Option: A

Pyrethrin is a natural plant derived substance that comes from the chrysanthemum cinerariaefolium.

Acid rain is caused by emissions of sulphur dioxide and nitrogen oxide, which react with the water molecules in the atmosphere to produce acids.

Correct Option: D

Acid rain is caused by emissions of sulphur dioxide and nitrogen oxide, which react with the water molecules in the atmosphere to produce acids.

A pungent smell often present near the urinals is due to ammonia.

Correct Option: C

A pungent smell often present near the urinals is due to ammonia.