The level of calcium in the blood of all healthy young adults follows a normal distribution with mean mu = 10 milligrams per deciliter (where mu stands for population mean) and population standard deviation 0.4. A clinic measures the blood calcium of 25 healthy pregnant young women at their first visit for prenatal care. The sample mean of these 25 measurements is 9.6. Is this evidence that the mean calcium level in the population from which these women come is less than 10? To answer this, test the hypotheses H 0 : mu = 10 versus H a : mu < 10. The p-value of your test is