(2)

Niagara Falls is the collective name for three waterfalls that straddle the international border between Canada and United States; more specifically, between the province of Ontario and the state of New York. They form the southern end of the Niagara Gorge.

From largest to smallest, the three waterfalls are the Horseshoe Falls, the American Falls and the Bridal Veil Falls. The Horseshoe Falls lies on the border of the United states and Canada with the American Falls entirely on the United States’ side, separated by Goat Island. The smaller Birdal Veil Falls are also on the United States’ side, separated from the other waterfalls by Luna Island.

Located on the Niagara River, which drains Lake Erie into Lake Ontario, the combined falls form the highest flow rate of any waterfall in North America that has a vertical drop of more than 165 feet(50m). During peak daytime tourist hours, more than six million cubic feet(168,000m³) of water goes over the crest of the falls every minute. Horseshoe Falls is the most powerful waterfall in North America, as measured by flow rate.

The falls are 17 miles(27 km) north-northwest of Buffalo, New York, and 75 miles (121 km) south-southeast of Toronto, between the twin cities of Niagara Falls, Ontario, and Niagara Falls, New York. Niagara Falls was formed when glaciers receded at the end of the Wisconsin glaciation( the last ice age), and water form the newly formed Great Lakes carved a path through the Niagara Escarpment en route to the Atlantic Ocean.

Niagara Falls is famed both for its beauty and as a valuable source of hydroelectric power. Balancing recreational, commercial, and industrial uses had been a challenge for the stewards of the falls since the 19^thcentury.

We can infer from the passage that ___ .