Ocean water is the least useful.
It passes through 13 countries, Ecuador, Colombia, brazil, sao tome, Gabon, congo, Uganda, Kenya, Somalia, Maldives, Indonesia, Kiribati.
SOS:
<u><em>Sierra Leone</em></u> is the answer!
<em>Hope this helps!!</em>
6x^2 + 3xy - 2xy +y^2
6x^2 + xy + y^2
