Answer :
Final answer:
In a Gallup poll survey at a 95% confidence level, the critical value is 1.96. This value corresponds to a standard normal probability distribution with a 2.5% tail, or a 95% confidence level.
Explanation:
In the field of statistics, the critical value is a point on the test distribution that is compared to the test statistic to determine whether to reject the null hypothesis. When it comes to a Gallup poll survey at a 95% confidence level, the critical value would be 1.96.
Here's why: A 95% confidence level means that we are confident that 95% of the results will fall within this range. In a standard normal probability distribution, this leaves 5% out beyond the confidence range, but this 5% is split evenly between the upper and lower tails of the distribution, each containing 2.5%. The critical value corresponding to the 2.5% in the tail (or the 95% in the middle) is approximately 1.96, hence answer a) is the correct answer.
Learn more about Critical Value here:
https://brainly.com/question/32607910
#SPJ11
