Answer:
Standard Deviation of D: It cannot be determined from the information given because the scores are not independent.
Explanation:
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What are the answers you can choose from?
Im not 100% sure, but i believe it's crop production will increase.
<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.