Because of their size, the tankers, for example, are however restricted to certain specific routes and are used to perform quite specific tasks in the form of supplying oil to highly centralised conurbations.
Ngenxa yobungakanani bazo, iitanki, umzekelo, ziqingqelwe iindlela ezikhethiweyo kwaye zisetyenziswa ukwenza imisebenzi ekhethiweyo ngokudlulisa loyile kwiinqumba zeedolophu ezisembini ezikudidi oluphe.