a$.$ Explain why a stack is usually described as a Last in First out $($LIFO$)$ data

structure.

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b$.$ A stack contains $4$ items. If the first item added to the stack is $7$ and the last

added item is $3.$

i$.$ What is the outcome of performing a Stack Top operation on the stack

after having performed four Stack Top operations?

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ii$.$ What is the outcome of performing a Stack Top operation on the stack

after having performed three Stack Pop operations?

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iii. What is the outcome of performing a Stack Pop operation on the stack

after having performed four Stack Pop operations?

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c$.$ Write algorithms $($pseudocode representation$)$ for the top, pop and push

operations of a stack.

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