C. The way the sample was chosen may overrepresent or underrepresent students taking certain language classes.
The samples he chose may not be a representative sample because the number of students per foreign language class may not be the same. Since classes have different numbers of students, one may have a very large number of students while another may have only a few. Taking equal number of students per class is not a representative sample because it doesn't represent the students correctly.
Answer: See explanation
Step-by-step explanation:
Based on the scenario in the question, the expression to calculate the number of boxes of sugar Alonso can buys will be:
= 2.75 + 11.50S ≤ 55
When solved further, this will be:
2.75 + 11.50S ≤ 55
11.50S ≤ 55 - 2.75
11.50S ≤ 52.25
S ≤ 52.25 / 11.50
S ≤ 4.54
He can buy 4 boxes of sugar
Answer: 40000
Step-by-step explanation:
The formula to find the sample size is given by :-
, where p is the prior estimate of the population proportion.
Here we can see that the sample size is inversely proportion withe square of margin of error.
i.e. 
By the equation inverse variation, we have

Given :


Then, we have

Hence, the sample size will now have to be 4000.
Answer:
y = √{(a - x)/2b}
Step-by-step explanation:
x=a-2by²
2by² = a - x
divide through by 2b
y² = (a - x)/2b
y = √{(a - x)/2b}