Answer:
are their answer choices or no ???
Using the binomial distribution, it is found that there is a 0.0328 = 3.28% probability that at least 2 of them choose the same quote.
<h3>What is the binomial distribution formula?</h3>
The formula is:


The parameters are:
- x is the number of successes.
- n is the number of trials.
- p is the probability of a success on a single trial.
In this problem, we have that:
- There are 6 students, hence n = 6.
- There are 20 quotes, hence the probability of each being chosen is p = 1/20 = 0.05.
The probability of one quote being chosen at least two times is given by:

In which:
P(X < 2) = P(X = 0) + P(X = 1).
Then:



Then:
P(X < 2) = P(X = 0) + P(X = 1) = 0.7351 + 0.2321 = 0.9672.

0.0328 = 3.28% probability that at least 2 of them choose the same quote.
More can be learned about the binomial distribution at brainly.com/question/24863377
Answer:
Part a
For the given study, the explanatory variable or independent variable is given as regularity or frequency of exercise. This variable is classify as categorical variable because variable is divided into two categories such as whether participant exercise 5 or more days a week or not.
Part b
For the given study, the response variable or dependent variable is given as frequency of colds. This variable is classified as quantitative variable because we measure the quantities or frequency of number of colds.
Part c
A confounding variable for this research study is given as incidence of upper respiratory tract infections that provides an alternative explanation for the lower frequency of colds among those who exercised 5 or more days per week, compared to those who were largely sedentary. This confounding variable is categorical in nature.