evidence: The Democratic Republic of the Congo,[b] also known as the DR Congo, the DRC, or Congo-Kinshasa, is a country in Central Africa. By land area the Congo is the second-largest country in Africa and the 11th-largest in the world. With a population of around 109 million, the Democratic Republic of the Congo is the most populous Francophone country in the world. The national capital and largest city is Kinshasa, which is also the economic center. The country is bordered by the Republic of the Congo, Central African Republic, South Sudan, Uganda, Rwanda, Burundi, Tanzania (across Lake Tanganyika), Zambia, Angola, the Cabinda exclave of Angola, and the South Atlantic Ocean. [...] As a result of its equatorial location, the DRC experiences high precipitation and has the highest frequency of thunderstorms in the world. The annual rainfall can total upwards of 2,000 millimetres (80 in) in some places, and the area sustains the Congo rainforest, the second-largest rainforest in the world after the Amazon rainforest. This massive expanse of lush jungle covers most of the vast, low-lying central basin of the river, which slopes toward the Atlantic Ocean in the west. This area is surrounded by plateaus merging into savannas in the south and southwest, by mountainous terraces in the west, and dense grasslands extending beyond the Congo River in the north. The glaciated Rwenzori Mountains are found in the extreme eastern region.