SORU: aşağıdaki parçaya göre cevaplayınız
According to the passage, the artificial lake, built for the Panama Canal, ----.
At one point, during what was still a time of hopeful
experimentation with nuclear technology, the US
considered using atomic bombs to blow a trench
through the isthmus of Panama. The idea was to
replace the 50-year-old Panama Canal, whose locks
were too narrow for the world's growing fleet of
super-tankers and aircraft carriers, with one that
would be more suited to modern conditions. The
problem was not just the size of the locks but their
very existence. Ships don't simply sail through the
Panama Canal; they have to be lifted 85 feet to the
elevation of the highest point along the way and then
brought down to sea level again. Each ship's trip
through requires 52 million gallons of fresh water,
more than most American cities use in a day, all of it
flowing through huge gravity-fed tubes. The source
of this water supply is a vast artificial lake whose
dam also provides the electrical power for the whole
operation. To fill up and empty a single lock takes 40
minutes on average, and when any one of the 12
locks shuts down for maintenance, ship traffic can
back up for days. Finally, with all that complicated
machinery, if the canal were to be sabotaged (as had
happened to the lockless Suez Canal in 1956),
correcting the damage might take years.