Determine whether the given value is a statistic or a parameter. After taking the first exam, 15 of the students dropped the class.

Identify the number as either continuous or discrete. The height of 2-year-old maple tree is 28.3 ft.

Identify the sample and population. Also, determine whether the sample is likely to be representative of the population. In a poll of 50,000 randomly selected college students, 74% answered "yes" when asked "Do you have a television in your dorm room?". Answer: Sample: the 50,000 selected college students; population: all college students; representative

Is the study experimental or observational? A sample of fish is taken from a lake to measure the effect of pollution from a nearby factory on the fish.

Is the study experimental or observational? A quality control specialist compares the output from a machine with a new lubricant to the output of machines with the old lubricant.

Identify which of these types of sampling is used: random, stratified, systematic, cluster, convenience. A sample consists of every 49th student from a group of 496 students.

Identify which of these types of sampling is used: random, stratified, systematic, cluster, convenience. A market researcher selects 500 people from each of 10 cities.

Identify the number as either continuous or discrete. The number of stories in a Manhattan building is 22.

Is the study experimental or observational? A doctor performs several diagnostic tests to determine the reason for a patient's illness.

Identify the number as either continuous or discrete. The number of freshmen entering college in a certain year is 621.