Please choose the correct ending to complete the given sentence: Home and Garden: [header] How to anneal copper [title] Connect the red welding torch hose to the acetylene tank, and the black hose to the oxygen tank. [substeps] The acetylene tank is used for starting the flame and the oxygen tank is used to continue feeding the flame and to control the intensity of the flame. [title] Put on your safety goggles.

Ending1: [substeps] Wearing safety goggles is a precaution necessary to ensure eye safety anytime you are working with open flames. [title] Switch on the acetylene by turning the valve halfway. Ending2: [step] Safety goggles will help you open your eyes during the process. You will use these only during the procedure, so don't bother putting on one without a certain safety number (such as 0am or 0pm). Ending3: [step] These will allow you to see clearly. [substeps] If you intend to use the oxygen hose only in stages and rather than sections, then make sure that the goggles are not fitted to the eyes of the sailor in question. Ending4: [step] Look for the proper safety goggles that will cover your eyes if you need to inspect an area with copper. Welding can be dangerous and you may need a smoking extinguisher or acetylene grill.

Answer format: ending1/ending2/ending3/ending4