This picture develops a clear understanding.

Yes, if the angle between the two vectors is more than 90o but less than 2700. (cosΘ is negative)
Materials show varying behaviors based on their Poisson's ratio. High Poisson's ratio materials (near 0.5) contract significantly sideways when stretched and expand when compressed, seen in substances like rubber. Low Poisson's ratio materials (near 0) undergo minimal width change during axial deformation, typical of metals and common engineering materials.
The answer is A
In the depletion layer, electrons combine with holes producing charge density so that region is depleted of charge carriers but it has charge density .
Conclusion: Neutral but still having non zero charge density .

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