4x100 distances

how far does someone actually run in the 4x100? for example, I run the first leg, how far is it from the start to the beginning of the exchange zone? I ran an 11.2 split handing off about 6 feet into the exchange zone, what does something like that equate to open?

Better yet to simplify thingsā€¦ how many meters are each zome large tirangle to large triangle.?"