Please choose the correct ending to complete the given sentence: Fixing bicycle: A man gives a tutorial on how to change a bike tube. The wheel is taken off, tire irons are put in, and the tube is removed. a new tube

Ending1: is inserted and is pumped up. Ending2: is placed, wheels are removed, and two toilet flushes are to be cleaned. Ending3: is installed, set up and flipped over to remove any damaged nut. Ending4: is inflated with oil, another tube is taken off, and a new tube is inflated, then the first one.

Answer format: ending1/ending2/ending3/ending4