I believe the answer is...
A magnifying glass will create a larger, virtual image because the glass is made of a convex lens.
A. Correlation coefficient is simply just a number that shows the strength of the correlation. (ranges from -1.0 -> +1.0)
<h2>Answer </h2>
Option A - Stratified sampling
<u>Explanation</u>
The student used Stratified sampling as in the following process the student divided the students of the high school into equal subgroups before sampling. Then a random sample is drawn from each group. Members in Sophomore, Junior, and Senior classes may not be fixed as they are picked on random bases. However, the objective is to improve the accuracy of the sample when the population size is too large.
