Young Adults at Risk. N. Kaseva et al. published a research paperentitled ‘‘Blunted hypothalamic-pituitary-adrenal axis and insulin response to psychosocial stress in young adults born preterm at very low birth weight’’ (Clinical Endocrinology, Vol .80, No. 1, pp. 101−106)].

It shows that young adults who were born prematurely with very low birth weights (below 1500 grams) have blunted insulin response compared to those born at term. The researchers found that the insulin content of young adults who were born prematurely with very low birth weights have mean 9.7 mU/l and standard deviation 1.9 mU/l.

a. Identify the population and variable.

b. For samples of 20 young adults who were born prematurely with very low birth weights, find the mean and standard deviation of all possible sample mean insulin content. Interpret your results in words.

c. Repeat part

(b) for samples of size 40.