A Researcher Is Investigating Which of Two Newly Developed Automobile $\mu _ { \mathrm { A } } - \mu \mathrm { B }$

question 65

Multiple Choice

A researcher is investigating which of two newly developed automobile engine oils is better at prolonging the life of an engine. Since there are a variety of automobile engines, 20 different engine types were randomly selected and were tested using each of the two engine oils. The number of
Hours of continuous use before engine breakdown was recorded for each engine oil. Suppose the following 95% confidence interval for $\mu _ { \mathrm { A } } - \mu \mathrm { B }$ was calculated: (100, 2500) . Which of the following inferences is correct?

• A) We are 95% confident that no significant differences exists in the mean number of hours of continuous use before breakdown of engines using oils A and B.
• B) We are 95% confident that the mean number of hours of continuous use of an engine using oil A is between 100 and 2500 hours.
• C) We are 95% confident that an engine using oil A has a higher mean number of hours of continuous use before breakdown than does an engine using oil B.
• D) We are 95% confident that an engine using oil B has a higher mean number of hours of continuous use before breakdown than does an engine using oil A.

---

Definitions:

Artificially Create Milestones

The practice of deliberately setting checkpoint goals in a project's timeline, even if they don't naturally align with the project's progression.

Undue Influence

An improper or wrongful pressure exerted on someone to coerce them into an action that might not be in their best interest.

Responsibility Matrix

A tool used to define and document roles and responsibilities of individuals or teams in completing tasks or deliverables in a project.

Management Style

The approach or method that a manager uses to accomplish objectives, motivate employees, and manage tasks and challenges.