Assume a certain species bird has average weight of [xbar] = 3.55 grams. Based upon previous studies, we can suppose that the weights of these birds have normal distribution with ? = 0.37 grams. For small group of 15 birds, find out the margin of error for the 70% confidence interval for average weights of such birds.
a. 0.05 grams
b. 0.10 grams
c. 0.52 grams
d. 0.01 grams
e. 1.04 grams