current research indicates that the distribution of the life expectancies of a certain protozoan is normal with a mean of 43 days and a standard deviation of 10.1 days. find the probability that a simple random sample of 36 protozoa will have a mean life expectancy of 48 or more days. a) 0.0015 b) 0.6897 c) 0.9985 d) 0.0030 e) 0.2015 f) none of the above