4. For each the following scenarios in (a) - (e), specify the correct hypothesis test you should use to analyze the data.

a. Isabel wants to examine whether a sample of 30 students will spend less time on social media after watching Netflix's "The Social Dilemma" by comparing their weekly average screening time before and after watching the documentary.

b. A real estate agent is helping his customers to decide whether they should buy a property inCharleston town or in Springfield town by indicating that the house price (in thousands USD) in Springfield town (M = 394, s = 90) is significantly lower than the house price in Charleston town (M = 693, s = 150).

c. A CEO at a marketing company examines the typing speed of his newly recruited employees by comparing their average typing speed (M = 34, s = 3) to the general typing speed of all employees ( = 40).

d. A scientist matches the movie rating of a sample of 10 young adults with the movie rating of a sample of 10 elderly adults to examine if the audiences' opinion about specific movies will change as they grow older.

e. Data for the amount of time spent listening to music in the USA in 2019 revealed that consumers spent an average of = 26 hours per week enjoying their favorite tunes, with a standard deviation = 4. A psychologist in a nursing home wants to know if the number of hours per week spent listening to music is significantly different in nursing home residents, who are all older than 65 years old and usually spent M = 6 hours per week listening to music.