In his 2003 speech at Rice University’s Energy & Nanotechnology Conference, the late Nobel Laureate Richard Smalley highlighted the ____ 10 problems for the next 50 years. In his list, ____ sits at the top, and water comes next. Now, with the price of solar power going down, the dawn of a new energy ____ is just around the corner. As a result, ____ is going to be the greatest challenge for humanity.But the water problem is _____. First, unlike coal and oil, water cannot be _____. Second, water is _____ with every other sector of society. Third, while water demands are growing, climate change is intensifying droughts and floods and water supplies are ____.There are solutions, such as building water-transfer aqueducts, hydroelectric dams, and desalination plants. But they may be incredibly _____. It will ____ for scientists to find affordable solutions to the water problem. Before that, everyone should do his or her bit to ____ water.