In the study, cited in the text, of the relationship between the ...

[yoooooman]

In the study, cited in the text, of the relationship between the amount of
  time a teacher spends smiling and the achievement level of the students, it was
  shown that
 
  a. the less time a teacher smiles, the better the students do on an
   achievement test
   b. the more time a teacher smiles, the better the students do on an
   achievement test
   c. the time a teacher spends smiling is independent of student achievement
   d. a smiling teacher causes a student to get better grades

Question 2

In order to make accurate population estimates, the sample must be
 
  a. very large
  b. representative of the population
  c. manipulated by the experimenter
  d. free of any possible sampling error

[joechoochoy]

Answer to Question 1

b

Answer to Question 2

b

[yoooooman]

Thank you!

[joechoochoy]

Happy to help