Congo is the only major river which crosses the equator twice. It is the second largest river in Africa after Nile and the second largest river in the world.

The concentration of salt in seawater (its salinity) is about 35 parts per thousand; in other words, about 3.5% of the weight of seawater comes from the dissolved salts.

The Nile can be defined as the longest river by virtue of total head water lenght I.e from where the river is officially called the “Nile". In regard to discharge rate and catchment area the Amazon triumphs the Nile. The Amazon however has a much longer source stream than the Nile.

New York City is known by many nicknames—such as “the City that Never Sleeps” or “Gotham”—but the most popular one is probably “the Big Apple.” How did this nickname come about? Although uses of the phrase are documented in the early 1900s, the term first became popular in the 1920s when John J.

Canada-United States Border. Stretching a massive 8,893 km, Canada and the United States share the longest border in the world.

The smallest continent is Australia. Therefore, the correct answer is (A) Australia. Australia is both a country and a continent, and it is often referred to as the "smallest continent" due to its relatively small landmass compared to other continents.

Brisbane is not a former capital of Australia. The other cities are all former capitals of their respective countries: 

Karachi: The capital of Pakistan from 1947 to 1959

Auckland: A former capital of New Zealand

Kyoto: A former capital of Japan

Brisbane was the capital of Australia before Canberra from 1842 to 1859.