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A geyser heats water flowing at a rate of 2.0 kg per minute from 30°C to 70°C. If geyser operates on a gas burner, the rate of combustion of fuel will be ______ g min⁻¹ [Heat of combustion = 8 × 10³ J g⁻¹, Specific heat of water = 4.2 J g⁻¹ °C⁻¹]

1. 42.00
2. 42
3. 42 g/min
4. 42 g min⁻¹

Correct answer: 42.00

Solution

The correct option is 42.00 because it accurately represents the calculated rate of combustion of fuel required to heat the water, ensuring precision in the measurement with two decimal places, which is standard in scientific reporting.

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