Write the next sentence in this paragraph:

How to fill an oxygen tank
Replace the oxygen if the pressure gauge is in the red.
The pressure gauge is the large gauge at the top of the oxygen tank. This gauge has a dial that indicates how full the oxygen tank is.

Pick your answer from: -If the dial points to the red area or just above the red area, it is time to refill your oxygen tank. Turn on both your oxygen concentrator and your fill system.. -The dial reads 9 feet (1.8 meters) per minute. In contrast, you can find your oxygen level at the bottom of the oxygen tank.. -The dial you use should be indicated on the tank's roof. If the dial reads " 100, " that means you are filling the tank too full.. -The dial will be labeled " 80-4 ". If your pressure gauge is in the yellow zone, you can use the lcm gauge here instead..
If the dial points to the red area or just above the red area, it is time to refill your oxygen tank. Turn on both your oxygen concentrator and your fill system.