Class B Drinking Water Practice Test, Categorized

1.An ion exchange softener contains 50 cubic feet of resin with a hardness removal capacity of 20,000 grains/cu ft of resin. The water to be treated has a hardness of 300 mg/L as CaCO 3. How many gallons of water can be treated before the softener needs to be regenerated? Select the closest answer. ................
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