A cereal maker labels boxes 500 grams. A regulator will act if the mean fill is systematically over 500 grams or under 500 grams. What type of test is called for?

A hospital says its new check-in system makes the mean wait time less than 15 minutes. Administrators are watching only for evidence that the mean is below 15 minutes. What tail is this test?

A bottling engineer suspects a machine fills bottles with more than the target mean of 2.0 liters. The evidence being watched for is overfilling only. What type of test is appropriate?

A school counselor tests whether a tutoring app changes the mean study time from 40 minutes per night. An increase or a decrease would both count as a change. What type of test is needed?

A farm trials fertilizer that it hopes will raise the mean tomato mass above 120 grams. The farmer is watching only for heavier tomatoes. What tail describes the test?

A clinic tests whether a scheduling change lowered the mean visit length from 30 minutes. Staff are looking only for evidence that visits are shorter. What type of test is called for?

A transit agency measures how many minutes each bus arrives after its scheduled time, with early arrivals counted as negative. It tests a claimed mean of 0 minutes. Early and late arrivals would both be a problem. What type of test fits this goal?

A water plant wants to show the mean chlorine level is below the limit of 2.0 mg/L. The test is meant to find evidence only of being under that limit. What tail is used?

A battery maker claims a new design has a mean life greater than 8 hours. The researcher is watching only for evidence that life exceeds 8 hours. What type of test is appropriate?

A bakery tests whether cookie masses differ from the labeled mean of 25 grams. Inspectors care about either underweight or overweight cookies. What type of test should be used?

A city tests $H_0:p=0.30$ against $H_a:p>0.30$ for the proportion of commuters who bike to work. What tail describes this test?

A gym tests $H_0:\mu =18$ against $H_a:\mu <18$ for mean treadmill time in minutes. What tail describes this test?

A survey tests $H_0:p=0.62$ against $H_a:p\ne 0.62$ for the proportion of students who ride the bus. What tail describes this test?

A factory tests $H_0:\mu =100$ against $H_a:\mu >100$ for mean cable strength in newtons. What tail describes this test?

A school tests $H_0:p=0.12$ against $H_a:p<0.12$ for the proportion of lunches wasted. What tail describes this test?

A lab tests $H_0:\mu =4.5$ against $H_a:\mu \ne 4.5$ for mean reaction time in seconds. What tail describes this test?

A dentist believes a new rinse brings the mean number of cavities per patient per year under 1.4 cavities. What alternative hypothesis states that belief?

A coach believes a training plan raises the mean running speed above 7.8 meters per second. What alternative hypothesis states that belief?

A parts vendor believes the proportion of defective bolts is different from 0.04, with either more or fewer defects being important. What alternative hypothesis states that belief?

A school nurse believes a handwashing program lowers the proportion of students absent on a day below 0.08. What alternative hypothesis states that belief?

A packaging manager believes a new wrapper increases the mean sealing time above 12 seconds. What alternative hypothesis states that belief?

A two-tailed test of $H_0:\mu =50$ against $H_a:\mu \ne 50$ gives a test statistic of $t=-1.9$. What area under the curve is the p-value?

A right-tailed test of $H_0:p=0.40$ against $H_a:p>0.40$ gives a test statistic of $z=1.6$. What area under the curve is the p-value?

A left-tailed test of $H_0:\mu =72$ against $H_a:\mu <72$ gives a test statistic of $t=-2.3$. What area under the curve is the p-value?