12 interesting riddles

Interesting Riddles
1. A fruit on a tree,a tree on a fruit?
2. Which is the most shocking city?
3. Which bow cannot be tied?
4. Which bet can never be won?
5. What kind of dress can never be worn?
6. Which ship has two mates, but no captain?
7. A white lady who sheds tears all the time?
8. The more you take that,the more you leave behind?
9. What has scales but cannot be measured?
10. Which two keys can’t open any doors?
11. What is found in the middle of both Australia and America?
12. What’s black when it’s clean and white when it’s dirty?