The proportion of items in a population that possess a specific attribute is known to be 0.70 . a. If a simple random sample of size n=100 is selected and the proportion of items in the sample that contain the attribute of interest is 0.65 , what is the sampling error? b. Referring to part a, what is the probability that a sample of size 100 would have a sample proportion of 0.65 or less if the population proportion is 0.70