Answer:
Step-by-step explanation:
Hello!
An observational study is one where the investigator has no control or intervenes on it. He just defines the variable of interest and merely collects and documents the information.
An experimental study or experiment is one where the investigator intervenes by defining the variable of interest and artificially manipulates the study factor. It is also one of its characteristics the randomization of cases or subjects in groups (two or more, depending on what is the hypothesis of study).
1)
In the first example, the researcher doesn't control anything about the experiment, he just asks the professional musicians their age.
This is an observational study.
2)
In this second example, there is also no intervention of the researcher, she just asks her employees where they eat their lunch. This example is also an observational study.
I hope you have a SUPER day!
Answer: D
Step-by-step explanation:
Answer:
The probability that the two rats are from the first litter is 14.28%, and the probability that the two rats are from the second litter is 34.28%.
Step-by-step explanation:
Since a cage holds two litter of rats, and one litter comprises one female and five males, while the other litter comprises seven females and two males, and a random selection of two rats is done, to find the probability that the two rats are from the same litter the following calculation must be performed:
6/15 x 5/14 = 0.1428
9/15 x 8/14 = 0.3428
Therefore, the probability that the two rats are from the first litter is 14.28%, and the probability that the two rats are from the second litter is 34.28%.
Given, a = 1
common difference = 3
Eighth term = a+(n-1)d = 1+(8-1)3
= 1 + 21 = 22
<em>Hope</em><em> </em><em>this</em><em> </em><em>helps</em><em> </em><em>:</em><em>)</em>
The equation is/// k = (1/4)j