问答题Americans are used to ordering things ranging from French fries to popcorn in small, medium or supersize. Now those same decision-making skills may become rueful in the bathroom, thanks to an innovative plumbing technology: dual-flush toilets. The new

Americans are used to ordering things ranging from French fries to popcorn in small, medium or supersize. Now those same decision-making skills may become rueful in the bathroom, thanks to an innovative plumbing technology: dual-flush toilets. The new invention is the industry’s latest attempt to help reduce water usage, a movement that hasn’t always gone smoothly. The last big toilet makeover came more than a decade ago, when the U.S. government decreed that new toilets should use just 1.6 gallons of water per flush, down from the 3.5-gallon standard. But consumers complained that it often took two or more flushes to clear the bowl; so many people preferred the old toilets that some plumbers imported them illegally from Canada.