1. Longest river   Yangtze   Hwang Ho   Mississippi-Missouri   Amazon   Ob Irtysh   Hint Half-n-half Clue   2. Smallest ocean in the world   Atlantic Ocean   Arctic Ocean   Indian Ocean   Pacific Ocean   South China Sea   Half-n-half Clue   3. Densest planet of the solar system   Mars   Earth   Neptune   Jupiter   Pluto   Half-n-half Clue   4. Largest bay (in terms of area)   Cardigan Bay   Bay of Bengal   San Diego Bay   Cape of Good Hope   Hudson Bay   Half-n-half Clue   5. Largest satellite (natural) of our solar system   Ganymede   Deimos   Moon   Sinope   Phobos   Half-n-half Clue   6. Satellite closest to the parent planet   Moon   Titan   Phobos   Enceladus   Charon   Half-n-half Clue   7. Hottest place on the Earth (for extended periods of time)   Al Aziziyah   Marble Bar   Sahara Desert   Death Valley, California   Dallol   Half-n-half Clue