Which statement(s) about statistical studies is true? I. A survey of all English classes in a high school would be a good sample to determine the number of hours students throughout the school spend studying. U. A survey of all ninth graders in a high school would be a good sample to determine the number of student parking spaces needed at that high school. m. A survey of all students in one lunch period in a high school would be a good sample to determine the number of hours adults spend on social media websites. IV. A survey of all Calculus students iu a high school would be a good sample to determine the number of students throughout the school who don't like math.

A survey of all students in one lunch period in a high school would be a good sample to determine the number of hours adults spend on social media websites.

Step-by-step explanation:

Statement : A survey of all students in one lunch period in a high school would be a good sample to determine the number of hours adults spend on social media websites.

Out of all the statements made, the above statement is the only statement which where the sampling does not suffer a selection bias. In the sampling cases considered for the other statements there is a selection bias occurring as the sample is picked completely from either English classes or ninth graders or Calculus students leading to a check in the randomness of these samples. Hence the resulting models might not represent the entire population efficiently.

step-by-step explanation:

you can add the two numbers and divide the result by 2. or you can find the gap between the two numbers and add half of this to the smaller number.

y=x+9

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step-by-step explanation: