In the Following Proof, Which Justification Is Correct for Line

question 91

Multiple Choice

In the following proof, which justification is correct for line 7? $\begin{array}{llcc} \text {(1) \( (x) (\sim \mathrm{N} x \supset \mathrm{B} x) \) } && \text {Premise } \\ \text { (2) \( (\exists y) \sim \mathrm{By} \) } & \text { \(I(\exists z) (\mathrm{N} z \quad \vee \sim \mathrm{C} z) \) } & \text { Premise/Conclusion } \\ \text { (3) \( \sim \mathrm{Ba} \) } &&2 \mathrm{EI} \\ \text {(4) \( \sim \mathrm{Na} \supset \mathrm{Ba} \) } && 1 \mathrm{UI} \\ \text {(5) \( -\mathrm{Na} 3 \) , } &&4 \mathrm{MI} \\ \text {(6) \( \mathrm{Na} \) } &&5 \mathrm{DN} \\\text { (7) \( \mathrm{Na} v \sim \mathrm{Cba} \) } &\\\end{array}$

• A)4 Imp
• B)6 Add
• C)6 Taut
• D)Assumption
• E)None of these answers are correct.

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Definitions:

Meninges

Protective membranes covering the brain and spinal cord.

Dura Mater

The outermost and toughest of the three membranes covering the brain and spinal cord.

Radial Nerve

A nerve that extends down the arm and is responsible for extending the wrist and fingers.

Ulnar Nerve

A nerve running along the inner side of the arm and forearm, extending to the hand, responsible for movement and sensation.