What's the op-amp's open-loop bandwidth...? Show me how to find this please

Question

The upper critical frequency of an op-amp’s open-loop response is 300 Hz. If the midrange gain is 180,000, what is the ideal gain at 300 Hz? What is the actual gain? What is the op-amp’s open-loop bandwidth?

Answer 1

Gain is just starting to roll off at 300 Hz, so it is 3db down, or 0.7 down or 126000.

open loop bandwidth is 300 Hz.

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