How do they wash the Taj Mahal?

Where is cold desert vegetation found? What River starts in an ice cave in Himalaya? How did river Marsyas get its name? How was the Thames River made? What layer of the ocean does the marlin live in? What areas in the world are fast becoming desert? How many people built Hoover Dam? Do they have castles in Yugoslavia? How do universal studios make their money? What is the area of Aggtelek National Park? Who were Abigail Adams family members? Which Latin American country shares with the US a long coastline in the gulf of Mexico? Where are the three main rivers in Greece? Where is Hunza Valley located? How is the girder bridge built? What machine are located in dams that produce electricity from falling water? Why do the government like having zoos? What is Australias largest desert? What to do when there is no light in your house? In which direction would you travel to get from mount Everest to thenile river?