Answer:
D
Step-by-step explanation:
1 mile = 5280 feet
81 * 5280 = 427680 feet per hour
1 hour = 3600 seconds
427680 / 3600 = 118.8 feet per second
118.8 * 15 = 1782 feet in 15 seconds
The conclusion drawn from the study is instance because the sample is homogenous and an experimental study was performed.
<h3>What is an experimental study?</h3>
An experimental study deals with a dependent variable and there is a dependent variable.
Also, a control is used to establish the validity of the results.
The dependent variable is the level of softness after treatment while the independent variable is the type of water softener used.
The conclusion drawn from the study is instance because the sample is homogenous and an experimental study was performed.
Learn more about the experiment:
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