A researcher calculates a 90% confidence interval of (3397, 3421) to estimate the population birth weight using a random sample of 84 babies born to mothers with gestational diabetes. She wants to compare this range to the average for the general population, known to be 3389 grams. Choose the best answer to describe the alternative hypothesis and the statistical conclusion.
a. A p-value is needed to make a statistical conclusion.
b. Ha: μ≠3389, using a significance level of .10, two-tailed, we reject the null hypothesis
c. Ha: μ>3389, using a significance level of .05, one-tailed, we reject the null hypothesis
d. Ha: μ≠3389, using a significance level of .10, two-tailed, we fail to reject the null hypothesis