Convert from electronvolt to marco [Spanish]

Unit Definition (electronvolt)
The electronvolt is a unit of mass used in particle physics. Mass and energy are related by Einstein's famous equation, E = mc². The constant c is the speed of light, 299.79 x 10E6 m/sec. An energy of 1 electronvolt is therefore equivalent to a mass of about 1.782 662 x 10E-33 gram, or about 1.073 544 x 10E-9 atomic mass unit.

Unit Definition (marco [Spanish])
The marco is a traditional units of weight in various countries of Western Europe. In each country the unit equals 1/2 the unit corresponding to the English pound. Thus the French marc equals 1/2 livre, 8 onces or about 244.75 grams; the Spanish marco equals 1/2 libra or about 230 grams; the German mark equals 1/2 pfund or about 280.5 grams; and the English mark equals 8 ounces or 226.8 grams. The English unit was used almost entirely for measuring precious metals.