o2 sensor on 2005 Mazda MPV

Whre is the o2 sensor located on this car and how do you get it off?Thanks

Asked by for the 2005 Mazda MPV
On a V6 engine there is an O2 sensor at each of the two exhaust manifolds and one at the rear or the catalytic converters. A scan tool is required to identify which sensor has failed. The tool will identify the as B1S1, B2S1, B1S2, which means bank one sensor one, bank two sensor one, bank one sensor two ect.....
They are removed using a special socket that slips around the sensor.