Which of the Following Is Not a Valid Postfix Expression

question 6

Multiple Choice

Which of the following is not a valid postfix expression?

• A) 5 4 +
• B) 6 5 4 + -
• C) 4 + 5
• D) 8 2 + 2 /
• E) all of the above are valid postfix expressions

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Definitions:

Catholic Participants

Individuals who practice the Catholic faith and may be involved in research or activities related to their religious beliefs.

Scowling

A facial expression characterized by lowering the eyebrows and frowning, often indicating displeasure, anger, or concentration.

Disproportionately Positive

This term may refer to an overly or excessively positive assessment or outcome relative to expectations or norms, but without context, its specific meaning can be unclear.

Disproportionately Negative

Having an excessive or unequal amount of negativity or adverse effects compared to positives.