Australia is a member of the British Commonwealth of Nations since 1901. Australia is a constitutional monarchy like Great Britain. Formally the head of the state is the Queen of Britain, represented by the Governor General. The Queen appoints the Governor General on the recommendation of the Australian Prime Minister. His role, like the Queen's, is symbolic. The head of government and the real head of the state is the Prime Minister. Australia is mostly plain; there are mountains in the east and south. The highest point is Mount Kosciusko in the Australian Alps. There is very dry in the east, too little rain. In Australia there are two big deserts, namely, the Great Sandy Desert and Great Victoria Desert. The country has two big rivers: the Murray and the Darling.