\displaystyle \textbf{Question 1: }\text{What is the difference between a Collection and a Set? Give reasons}
\displaystyle \text{to support your answer.}
\displaystyle \textbf{Answer:}
\displaystyle \text{A Collection is the root interface of the Java Collections Framework that}
\displaystyle \text{represents a group of objects. It allows duplicate elements unless restricted}
\displaystyle \text{by a specific implementation.}
\displaystyle \text{A Set is a sub-interface of Collection that stores only unique elements and}
\displaystyle \text{does not allow duplicate values. Two Set objects are considered equal if they}
\displaystyle \text{contain the same elements.}
\displaystyle \\

\displaystyle \textbf{Question 2: }\text{Which of the following collections are sets? Justify your answer.}
\displaystyle \textbf{Answer:}
\displaystyle \text{(i) A collection of all natural numbers less than }50\text{: It is a SET because it is well-defined.}
\displaystyle \text{(ii) The collection of good hockey players in India: It is NOT a SET because it is not well-defined.}
\displaystyle \text{The word 'good' is subjective and may vary from person to person.}
\displaystyle \text{(iii) The collection of all girls in your class: It is a SET because it is well-defined.}
\displaystyle \text{The members of the collection can be identified exactly.}
\displaystyle \text{(iv) The collection of most talented writers in India: It is NOT a SET because it is not well-defined.}
\displaystyle \text{The term 'most talented' is subjective.}
\displaystyle \text{(v) The collection of difficult topics in Mathematics: It is NOT a SET because it is not well-defined.}
\displaystyle \text{The difficulty of a topic varies from one student to another.}
\displaystyle \text{(vi) The collection of all months of a year beginning with the letter }J\text{: It is a SET because it is well-defined.}
\displaystyle \text{The set is }\{\text{January, June, July}\}.
\displaystyle \text{(vii) A collection of novels written by Munshi Prem Chand: It is a SET because it is well-defined.}
\displaystyle \text{The novels written by Munshi Prem Chand are known and can be listed.}
\displaystyle \text{(viii) The collection of all questions in this chapter: It is a SET because it is well-defined.}
\displaystyle \text{The questions in the chapter are fixed and can be identified.}
\displaystyle \text{(ix) The collection of most dangerous animals of the world: It is NOT a SET because it is not well-defined.}
\displaystyle \text{The term 'most dangerous' is subjective.}
\displaystyle \text{(x) The collection of prime integers: It is a SET because it is well-defined.}
\displaystyle \text{The set of prime integers is }\{2,3,5,7,11,\cdots\}.
\displaystyle \\

\displaystyle \textbf{Question 3: }\text{If }A=\{0,1,2,3,4,5,6,7,8,9,10\},\text{ insert the appropriate symbol }
\displaystyle \in\text{ or }\notin\text{ in each of the following blank spaces.}
\displaystyle \textbf{Answer:}
\displaystyle \text{(i) }4\in A\qquad\text{(ii) }-4\notin A\qquad\text{(iii) }12\notin A
\displaystyle \text{(iv) }9\in A\qquad\text{(v) }0\in A\qquad\text{(vi) }-2\notin A
\displaystyle \\

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