<span>tsunamis,volcanoes,destructive earthquakes and hurricanes </span>
A car was invented to run on only water and nothing else so that the air pollution can be decreased because then no smoke would come out of the exhaust.
An ocean current is a continuous movement of water in the ocean in some direction - this means that the water flows at a similar speed and direction despite the fact that it's not the same water - i.e. there is a water exchange in the current. The currents are caused by such factors as temperature and salinity of water.
