What type of procedure should we use for each scenario, one sample z testfor a mean, one sample t testfor a mean, or a matched pairs t testfor a mean difference?

Scenario 1:

A company would like to estimate the average commute time of their employees to work. They take a random sample of 40 employees and ask them how long their commute is in minutes. The sample yields an average of 38 minutes and a standard deviation of 8 minutes. From this they would like to calculate a 95% confidence interval.

This scenario should use a

Scenario 2:

A factory that produces milk randomly tests the fat content of batches of milk that is supposed to be 2% milk fat. To test the jugs they take a random sample of 5 jugs per batch.The company knows the milk fat in the population varies on average 0.1%. Their sample yields a sample mean of 2.02%.

This scenario should use a

Scenario 3:

Aentomologist is analyzing the venom of worker bees. She would like to know if the average histamine content is greater than 300 nanograms. The following is data on histamine content in nanograms from 7 eight day old worker bees: 649, 832, 418, 530 , 384, 899, 755.

This scenario should use a

Scenario 4:

Josh has a feeling his fitness tracker is counting too many steps. He decides to wear both a general pedometer and his fitness tracker for 5 days. He is curious if their is evidence average difference between the trackers is different than zero. Below are his measurements.

Day	1	2	3	4	5
Fitness Tracker	9910	11008	7006	9571	12531
General Pedometer	9569	10937	6998	9374	11788