Moderately hard water has hardness level -

Ans. is 'b' i.e., 1-3 Classification of hardness in waterClassificationLevel of hardness (mEq./litre)a) Soft waterb) Moderately hardc) Hard waterd) Very hard waterLess than 1 (< 50 mg/L)1 -3 (50- 150 mg/L)3 -6(150-300 mg/L)Over 6 (> 300 mg/L)