Please choose the correct ending to complete the given sentence: Computers and Electronics: [header] How to turn an old road bike into a singlespeed [title] Check the rear dropout shape. [step] Does the bike have horizontal dropouts in the back? This is necessary to be able to adjust chain slack in the final step. Alternately, you can buy some kind of doohickey to do it, but that ruins the clean look so vitally important to most conversions.

Ending1: [title] Place a knee-high wheel on one of the downsides of the road. [step] This may be considered a " footstool, " because someone else will be riding the bike for the first time. Ending2: [substeps] If the bike is on axle, sit down and count to 10. If it is on kickstand, get some form of tape with knots, and wrap it all the way around the handlebars. Ending3: [title] Know what to do? [step] Making the road bike stand up is intuitive; just stay in the centre of the road in readiness for the next turn. Look to the opposite side for a possible way to adjust chain slack. Ending4: What this means is, can you adjust where the back wheel goes, in a front-back direction. Some bikes have vertical dropouts, some have slanted ones.

Answer format: ending1/ending2/ending3/ending4