Respuesta :
The statement second and statment third are the reason that method used might be biased.
It is given that Adam gives a survey postcard to every twentieth student that enters the building.
It is required to find the statement why the method used to be biased.
What is the sample size?
The sample size is nothing but the number of observations in an activity or participants generally it is represented by the small letter 'n'.
Adam gives a survey postcard to every twentieth student, not every student that enters the building.
It means asking every twentieth student does not represent the student population.
Also, the opinions of students at one high school do not exactly reflect the opinions of students at other high schools.
Students that take the time to fill out the survey and send it in are likely passionate about hot lunches.
Thus, the statement second and statment third are the reason that method used might be biased.
Learn more about the biased sample here:
https://brainly.com/question/26962814