What quantity of water should taken out to concentrate 15 liters of 40% acidic liquid to 60% acidic liquid? Select:  A) 5 liters  B) 10 liters  C) 15 liters  D) 8 liters  E) 6 liters

Rationale: required answer is = 15 ( 60 - 40 ) / 60 = 5 liters answer is a
Answer: A