A Statistics Teacher Wants to See If There Is Any $\begin{array}{ll}&\text { Today } & \text { Five Years Ago } \\\bar {x}&82 & 88 \\\sigma^2&112.5 & 54 \\n&45 & 36\end{array}$

question 25

Multiple Choice

A statistics teacher wants to see if there is any difference in the abilities of students enrolled in statistics today and those enrolled five years ago.A sample of final examination scores from students enrolled today and from students enrolled five years ago was taken.You are given the following information. $\begin{array}{ll}&\text { Today } & \text { Five Years Ago } \\\bar {x}&82 & 88 \\\sigma^2&112.5 & 54 \\n&45 & 36\end{array}$
The standard error of $\bar { x } _ { 1 }$ - $\bar { x } _ { 2 }$ is

• A) 12.9.
• B) 9.3.
• C) 4.
• D) 2.

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Definitions:

Price-Fixing

An illegal agreement among competitors to set prices, establish production quotas, or engage in other practices that eliminate or reduce competition within an industry.

Anticompetitive Mergers

Mergers between companies that could reduce competition in an industry, potentially leading to higher prices and reduced innovation.

Natural Monopoly

occurs when a single firm can supply a product or service to an entire market at a lower cost than could two or more firms, often due to high fixed or startup costs.

Public Ownership

The ownership of assets by the government or state, as opposed to private individuals or organizations.