Refer to this design web of a car manufacturer’s experiment. Which of the following statements are true? Check all that apply. A confounding variable is the use of cruise control.
A confounding variable is the weather conditions.
A confounding variable is the participants’ reporting on their fuel efficiency.
There are no confounding variables in this experiment.
A confounding variable is the speed at which the participants drive on the course.

2,3,5

B,C,E

A confounding variable is the weather conditions.

A confounding variable is the participants’ reporting on their fuel efficiency.

A confounding variable is the speed at which the participants drive on the course.

ED2021

d

step-by-step explanation:

i used the pitagoras theoreme

d. 24+-0.114

step-by-step explanation:

the question requires us to calculate the approximate 95% confidence interval for the mean number of ounces of ketchup per bottle in the sample given the following statistics;

sample mean = 24

standard deviation, σ = 0.4

sample size , n = 49

the confidence interval for a population mean is calculated using the formula;

sample mean ± z-score*(σ/sqrt(n))

the z-score associated with a 95% confidence interval, from the standard normal tables, is;

1.96

substituting these values into the formula;

24 ± 1.96*(0.4/7)

= 24 ± 0.112

from the alternatives given, choice d is closest to the above expression;