Chemical element of metals. Cu comes from Cuprum, Fe comes from Ferrum, Ag from Argentum. The symbols were not followed by a period (full stop) as with abbreviations. Later chemical elements were also assigned unique chemical symbols, based on the name of the element, but not necessarily in English. For example, sodium has the chemical symbol 'Na' after the Latin "natrium". The same applies to "W" (wolfram) for tungsten, "Fe" (ferrum) for iron, "Hg" (hydrargyrum) for mercury, "Sn" (stannum) for tin, "K" (kalium) for potassium, "Au" (aurum) for gold, "Ag" (argentum) for silver, "Pb" (plumbum) for lead, "Cu" (cuprum) for copper, and
Au pair well as an insurance for potential repatriation costs for the au pair. In Belgium, an au pair is entitled to at least 450 euros pocket money per month, deposited to her bank account. The au pair is entitled to the full amount of monthly pocket money in cases of illness and during holidays. Au pairs are not allowed to work more than 4 hours a day (babysitting hours included) and 20 hours per week, spread out over a maximum of 6 days a week. Au pair are entitled to at least one day off per week and at least one