The relative humidity in an incubator is usually set at? by Sunday | Dec 20 | Agricultural Science WAEC | 0 comments A. 10% – 30% B. 40% – 60% C. 70% – 80% D. 90% – 100%. Correct Answer: Option B = 40% – 60% Users Also Read These:The mass of water vapour in a given volume of air is…The instrument used for measuring relative humidity…Which of the following is used to measure relative humidity?A relative humidity of 100 percent means that air is?Which of the following instruments is used to…