Convert from teragram to arroba [Portugal]

Unit Definition (teragram)
The teragram is a metric unit of mass equal to 1012 grams or 1 megatonne (one million metric tons). This unit is frequently used in atmospheric science and other scientific contexts where large masses are considered.

Unit Definition (arroba [Portugal])
The arroba [Portugal] is a traditional unit of weight in Spain and Portugal, equal to 1/4 quintal. However, the Spanish and Portuguese quintals are of different sizes. In Portugal and Brazil, the arroba traditionally equals 32.38 pounds (14.69 kilograms, but in recent years this has been "metrized" to be exactly 15 kilograms). The arroba has also been used as a metric unit equal to exactly 15 kilograms. The name of the unit comes from ar rub', Arabic for "the quarter."