Question

a journalism student is writing an article about her schools new cell-phone policy, and shed like to interview a random sample of students. which of the following is the best example of a random sample?

the writer arrives at school early and interviews the first five students who come through the main entrance.

the writer passes out brief surveys to 50 students in the hall and uses the 18 surveys returned to her as the basis of her article.

the writer asks her teacher if she can distribute a brief survey to the students in her ap psychology class.

the writer pulls the names of five students from a hat that contains all studetns names. she interviews the five selected students.

pregunta 22
1 puntos
which of the following is a positive correlation?

the more people exercise, the better they sleep.

as study time increases, students achieve lower grades.

gas mileage decreases as vehicle weight increases.

as levels of self - esteem decline, levels of depression increase.

Explanation:

First Question (Random Sample)

• Option 1: Interviewing the first five students at the main entrance is a convenience sample (biased, as it's not random—depends on who arrives early).
• Option 2: Using returned surveys is a voluntary response sample (biased, as only those who choose to return surveys are included).
• Option 3: Surveying only AP Psychology class students is a convenience or cluster sample (biased, as it's a specific class, not representative of all students).
• Option 4: Pulling names from a hat with all students’ names ensures each student has an equal chance of being selected, which is a simple random sample.

• Positive correlation means as one variable increases, the other also increases.
• Option 1: More exercise → better sleep (both increase: positive correlation).
• Option 2: More study time → lower grades (one increases, the other decreases: negative correlation).
• Option 3: Vehicle weight increases → gas mileage decreases (one increases, the other decreases: negative correlation).
• Option 4: Self - esteem declines → depression increases (one decreases, the other increases: negative correlation).

Answer:

D. The writer pulls the names of five students from a hat that contains all students' names. She interviews the five selected students.

Second Question (Positive Correlation)