In the Following Proof, Which Justification Is Correct for Line

question 49

Multiple Choice

In the following proof, which justification is correct for line 3? $\begin{array}{llcc} \text { (1) \( \sim \mathrm{Da} \) } &&\text { Premise} \\ \text { (2) \( (x) (\sim \mathrm{C} x \supset \mathrm{D} x) \) } & \text { \(/ \mathrm{Ca}\) }& \text { Premise/Conclusion } \\ \text { (3) \( \sim \mathrm{Cb} \supset \mathrm{Db} \) } &\\\end{array}$

• A)1 Add
• B)2 UI
• C)Assumption
• D)1, 2 MT
• E)None of these answers are correct.

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Definitions:

Memory Span

The amount of information or number of items that an individual can hold in short-term memory at one time.

Cognitive Psychologist

A professional specializing in the scientific study of mental processes such as perception, thought, memory, and reasoning.

Thinking

The mental process of generating ideas, reasoning, and solving problems.

Translating

The process of converting text or speech from one language to another while preserving its original meaning as closely as possible.