A COVID-19 study was conducted to learn how long it takes to recover from mild COVID-19 and found that, on average, it takes 9 days for a person to recover from it. A random sample of 25 adults with mild COVID-19 was selected. The sample mean was 11 days, with a standard deviation of 4.5 days. Assume the sample is normally distributed. Using alpha = 0.01, test whether the average days to recover is more than 9 days.

Group of answer choices

The test statistic is -2.71, and the critical value is -1.30, we reject H0.

The test statistic is 2.21 and the critical value is 1.96, we reject H0

The test statistic is -1.03, and the critical value is -1.96, we fail to reject H0.

The test statistic is 2.22, and the critical value is 2.492, we fail reject H0.