Convert from oxgang to barn

Unit Definition (oxgang)
The oxgang is an old English unit of land area equal to 1/8 hide or roughly 15 acres (6 hectares). The hide was considered the area a farmer could plow with a team of 8 oxen, so an oxgang was the area he could plow with a single ox. The unit was also called the bovate, from the Latin word bos for an ox or cow.

Unit Definition (barn)
The Barn is a slightly humorous unit of area used in nuclear physics. When atoms are bombarded with smaller particles such as electrons, the electrons are scattered as if the nucleus of the atom was a tiny solid object. The barn is used to express the apparent cross-sectional area of this scattering object. One barn is equal to 1E-28 square meters. Using this unit, physicists can say that such and such a nucleus is "as big as a barn", or 10 barns, or whatever. The proper SI unit to use for these measurements is the square femtometer (fm²); one barn equals 100 fm².