USA HISTORY

Detailed explanation-1: -Lake Elevation Lake Mead began filling in late 1934 and the average daily surface elevations from 1 February 1935, when elevation data began to be collected, through 2009 are shown in Figure 2. The reservoir did not reach 1, 045 ft above msl, the elevation of the upper outlet, until 1 May 1937.

Detailed explanation-2: -Created by the Glen Canyon Dam, picturesque Lake Powell encompasses almost 2000 miles of shoreline and spans an impressive 186 miles in length. It’s so massive that it took almost 14 years to fill the lake after the dam’s completion in 1963, and another four years to reach its capacity.

Detailed explanation-3: -It began filling upon the completion of Hoover Dam (previously known as Boulder Dam) in 1935. The largest hydroelectric dam in the world at the time of its construction, Hoover Dam was completed in less than five years. It stretches across the Colorado River at Black Canyon, about 30 miles east of Las Vegas.

Detailed explanation-4: -The correct answer is 47 days. Since the lily pads double every day, if the pond is half-full after 47 days, then it doubles and gets filled the very next day, the 48th.