A) No
B) Yes

question 2

Multiple Choice

$$\begin{array}{l}\text { Is the system shown closed under the operation? }\\\begin{array} { c | c c c c } * & q & r & s & t \\\hline q & t & s & r & q \\r & s & q & t & r \\s & r & t & q & s \\t & q & r & s & t\end{array}\end{array}$$

• A) No
• B) Yes

---

Definitions:

Competition

The effort and striving between two or more independent rivals to secure the business of one or more third parties by offering the best possible terms.

Quantity Traded

This refers to the total amount of a certain commodity, security, or currency that is transferred over a given period.

Gold

A precious metal used historically as a store of value, for investment, and in various industrial and technological applications.

Ethanol

A volatile, flammable, colorless liquid alcohol used as a fuel additive and in alcoholic beverages.