1st Example: Combustion heater

A heater warms up water using butane, with a heating value of pc=MJ/kg, and it has an efficiency of η=%, providing a flow rate of q=L/min while causing an increase in its temperature of Δt=℃. Butane is obtained from gas cylinders holding mb=kg, which cost cb=€. Water's specific heat is of cp=J/(g K). Under these conditions, determine:

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