ThebasicflagoftheUnitedStatesisoneoftheworld’soldestnat...
问题详情：ThebasicflagoftheUnitedStatesisoneoftheworld’soldestnationalflags.OnlythebasicflagsofAustria,Denmark,GreatBritain,theNetherlands,Sweden,andSwitzerlandareolder.Duringthediscoveryandsettlemento...