Answer:
Is an experimental study
Step-by-step explanation:
In an observational study you don't control any aspect of the investigation you just observe the variables that you determined since the beginning without any intervention.
In this case you are controlling who sees one or the other video, then you are controlling one of the variables that is the type of video each group sees and because of this it is an experimental study. Researchers designed an experiment to prove the null hypothesis they had.
The answer to the question mentioned above is "the mean" such as the whole sentence will become "The horizontal value at which the highest point of a variable's normal curve is also the MEAN of the variable". This is the answer.
First, create a rule for this sequence.
Let a(1) be the first term (which here happens to be 1).
The next term, a(2), is twice the previous term, that is, twice 1, or 2.
a(3) = 2a(2) = 2(2) = 4
This is called a "recursive function."
The 3rd term is 4. The next, which is a(3) is 2*4, or 8.
Note that there's an alternative approach. The first term, a(1), is 1; the next is a(2) = a(1)*2^(2-1) = 1*2^1=2
the next is a(3) = 1*2^(3-1) = 1*2^2 = 4
So the rule is a(n) = a(1)*2^(n-1).
So a(8) is a(1)*2^(8-1) = 1*2^7 = 2^3*2^4 = 8(16) = 128
