11) Which desert features the world's tallest sand dunes?
12) In which desert is the world's longest river located?
13) The Kalahari desert spans which two countries?
14) What is the hottest desert in the world?
15) What is the largest desert on Earth?
16) What type of climate is typical of a desert?
17) What type of precipitation do deserts usually get?
18) What are small, round depressions in the ground called in a desert?
19) What is the driest desert in the world?
20) What is the coldest desert in the world?