the 10 idioms with meaning are :
1. piece of cake - to get an easy task which would be easy to complete.
2. pull a rabbit out of the hat - to do something unexpected.
3. backed him/her up - to give the support.
4. to come back to the earth - to stop dreaming.
5. turned over a new leaf - began a different mode of the life.
6. break a leg - good luck.
7. she/he was bit muzzy - confused.
8. best way of spirits - a good remark on an person.
9. the sun rises and sets on you - a wonderful person.
10. a penny of your thought - to ask some one what is he/she is thinking.