Please choose the correct ending to complete the given sentence: Home and Garden: [header] How to build and operate a fullly automated ceramic pyrolisy stove for indoors [title] Build a pipe out of 3 mm thick iron or 10 mm thick ceramic. [step] The interior diameter should be 100 mm or more and the length should be 200 mm with a bottom. Don't forget to put another piece of pipe beneath the bottom and cut a fuel chops entry in the bottom section, crenelating the top accordingly.

Ending1: Here's how to do it : [substeps] Place the piece of charcoal to either side of the first layer of coals. Push a steel press down towards the coals. Ending2: [title] Grate the starter so as not to break the pipe. [step] Once it is full once removed grate it into the bottom pipe as soon as you can. Ending3: [title] Mark the pipe except for a water pipe. [title] Repeat the steps with either pipes or fuel chops the same diameter each. Ending4: The pipe should be at least twice as tall as wide. [title] Build the conic lid to fit over the top.

Answer format: ending1/ending2/ending3/ending4