96 Max, O2 sensor, Bank 2 sensor 1, which is it?

Need to replace an O2 sensor on my 96 Max, The code is P0150, O2 sensor Bank 2 sensor 1.
Question is which sensor is it? I believe there are 3.

Any help appreciated.

Thanks
Craig

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Yes, there are three Oxygen Sensors. Two upstream sensors positioned in front of the Catalytic converter and one downstream sensor positioned behind the Catalytic converter. More frequently one or both of the upstream sensors are failing. I would replace both upstream sensors. That way, you'll only have get up in there once. The upstream sensors can be had for as little as $65.oo each.