Answer:
Randomized
Explanation:
Observational Studies and Randomized Trials are two ideal ways of determining the outcome of certain tests.
In the Observational course the study is conducted in a true to life scenario and the result of what happens is recorded. Meanwhile, in the Randomized Trial there purposefully placed conditions that are ideal and these are evaluated after specific interventions.
Since the pool manager did not let different pools grow algae at will before putting in the chemical this study would not be considered observational. Instead he set up three different pools of the same size with the similar amount of contaminants and then tested the algaecide. This classifies this as a Randomized Trial.
Ideas and content <span>refers to one of the six writing traits that addresses the thesis, opinion, or theme.
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The sentences that contribute to a sense of hope are "<span>She could see in the open square before her house the tops of trees that were all aquiver with the new spring life. The delicious breath of rain was in the air. In the street below a peddler was crying his wares. The notes of a distant song which someone was singing reached her faintly, and countless sparrows were twittering in the eaves. There were patches of blue sky showing here and there through the clouds that had met and piled one above the other in the west facing her window." First of all, she sees trees that are trembling with new life. A peddler was selling his goods. She could hear a distant song which someone was singing, and songs usually mean good spirit in works of literature.
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