The correct answer is B
These students do not represent the whole population of students, so the results of the survey will disproportionately recognize the opinion of the extracurricular students.
The letter "x" is often used in algebra to mean a value that is not yet known. It is called a "variable" or sometimes an "unknown". In x + 2 = 7, x is a variable, but we can work out its value if we try!
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50 times 5 =250
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