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A1 We consider the edge of the field to be the part floating from the floor of the field, such as the ramp, the tile elevated by the ramp, or the seesaw.
A2 When thinking about the rules, the center is the standard. However, when organizing the world competition, we measure from the edge of the black line in favor of the team.
A3 We also consider Ramps and seesaws to be on the edge of the field, so keep obstacles 25 cm away from the seesaw. … The seesaw is also an inclined tiles like as Ramps.
A4 Yes.
A5 Yes. We have a similar question here.