The haemoglobin levels of pregnant females in a community was found to have a mean of 10.6 g/d1, and a standard detion of 2 g/dL. What is the minimum haemoglobin level below which 5% of the pregnant females will have their haemoglobin levels?
(A) 7.32 (B) 8.64 (C) 6.68 (D) 8.96
(C) Ans. c. 6.68