The answer of you're question is C
Answer:
C
Step-by-step explanation:
The substance in the second beaker must have lost heat for it to solidify
The sample used in this problem is classified as cluster.
<h3>How are samples classified?</h3>
Samples may be classified as:
- Convenient: Drawn from a conveniently available pool.
- Random: All the options into a hat and drawn some of them.
- Systematic: Every kth element is taken.
- Cluster: Divides population into groups, called clusters, and each element in the cluster is surveyed.
- Stratified: Also divides the population into groups. Then, a equal proportion of each group is surveyed.
For this problem, a group of schools is selected, and then the new program is applied to all students in these school, meaning that all elements in the cluster are surveyed, so cluster sampling is used.
More can be learned about classification of samples at brainly.com/question/25122507
#SPJ1
