Please choose the correct ending to complete the given sentence: Work World: [header] How to build a window farm [title] Have one empty bottle for each type of plant. [title] Cut off the bottoms of each bottle with the blade. [title] Hold each bottle inverted (neck down) and place a few clay fired pebbles into the bottles through the sliced-off bottom.

Ending1: [step] The pebbles will be the base of the farm. [title] Build one small room using 8 square foot (0.59 square m) plywood blocks, a few cinder blocks, and a few stakes, placing them sporadically around the center of the farm. Ending2: [step] If the pellets have a tendency to fall out of the bottle's mouth, place a piece of cloth in the neck and then add the pebbles. These pebbles act as soil, holding enough water for the roots and also allowing for air to pass. Ending3: [step] It does not matter which end the pebbles come out of. [title] Use the air-bags that came with the soil packs. Ending4: [title] Glue on any concrete pieces you find. [title] Repeat this method for every type of plant you find.

Answer format: ending1/ending2/ending3/ending4