The concentration of pollutant A in a river with a total flow rate (freshwater + wastewater) of 50 m3/s is 10 mg/L. This problem occurred after a wastewater stream from an industrial facility with a flow rate of 50 L/s was sent to the river. Assuming the river had an initial concentration of 1 mg/L for the pollutant A, what is the concentration of A in the wastewater stream (g/L)?