In this task you are given a sentence with one coordinating conjunction (for, and, nor, but, or, yet, and so). You must judge whether the order of two coordinated clausal conjoints have been inverted or not. Inversion would result in the sentence sounding unnatural. Label the instances as "Original" or "Inversion" based on your judgment.

The pilot scrambled to open the hatch , and surprisingly cold air washed down on them .
Original

Many of the occupants were staring at them , and the bar was a U-shape , with perhaps thirty seats .
Inversion

When he opened it my bleak mood lifted for a moment , and we walked down a dim brick hallway to a steel door .

Inversion