Answer:
a) Observational study
b) No
c) No
-Eating habits
-Age
-Health hystory
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. These types of studies are usually made as precursors to a more formal experimental study, to have an idea of what's to be expected from the population.
In this example, the researcher merely took the information of interest from the survey that was taken. The researcher did not intervene in any way in the experiment. Because of the lack of intervention from the researcher, it is not valid to use the conclusions of this experiment to generalize to all American adults. For instance, it is not sure that the sample is representative, all people responding to the survey may be healthy or have certain eating habits. This also shows that many confusing factors are not taken into account like:
-eating habits (from eating healthy to extreme cases like being vegetarian/vegan or eating only fast food)
-age, the age range is not defined, if the sample is taken from surveys answered by people in their early 20s it will be different in both eating habits and health information as if the interviewees are in their 30s or 40s
-before health issues, there can be other health conditions that may be affecting the interviewees.
I hope it helps!
As long as your indexes are the same (which they are; they are all square roots) and you radicands are the same (which they are; they are all 11), then you can add or subtract. The rules for adding and subtracting radicals are more picky than multiplying or dividing. Just like adding fractions or combining like terms. Since all the square roots are the same we only have to worry about the numbers outside. In fact, it may help to factor out the sqrt 11:

. The numbers subtract to give you -9. Therefore, the simplification is
The answer is the first one
Answer:
the answer is x ≥ 3, just put the line under the sign and your good
Step-by-step explanation:
An equilateral triangle cross section can be obtained by cutting the cube by a plane defined by the midpoints of the three edges emanating from any one vertex.