Question

why would you need to purge a cylinder? select all that apply. the cylinder was not purged by the manufacturer. the cylinder was opened to the atmosphere. the cylinder still has some propane in it.

Explanation:

Purging a cylinder is done to remove contaminants or unwanted gases. If the cylinder was not purged by the manufacturer, it may contain impurities. When a cylinder is opened to the atmosphere, air (and its components like oxygen, nitrogen etc.) can enter, so it needs to be purged. The presence of some propane remaining does not necessarily mean it needs purging as long as the propane is pure and there are no contaminants.

Answer:

The cylinder was not purged by the manufacturer.
The cylinder was opened to the atmosphere.