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1) https://www.britannica.com/science/are
The are is a basic unit of area in the metric system, equals to 100 square meters.
2) https://en.wikipedia.org/wiki/Hectare
The hectare is an SI accepted metric system unit of area equal to a square with 100-meter sides, or 10,000 m2.
After providing this info, I am in position now to solve the problem.
To get the time to complete the job, take the total area 3.03 hectares, convert it to ares
3.03 hectares = 303 ares
subtract the area of the warehouse
303 ares -
ares = 303 - 3 = 300 ares
and divide it by 42
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