Lots of questions about mario kart ds

[MarioVet]

i have some questions... a lot of questions... some one please answer them ;-;.

1. Does the item stat apply online?
2. do any stats apply online?
3. do certain chars find more of an item? (i.e. toad finds more mushrooms)
4. Is weight the stat that affects how hard it is too turn or is it handle?
5. What does drift do?
6. what is the best cart? (i dont want an opinionated question, i want a fact )
7. Is there even a best cart?
8. Why do people say R.O.B. is the best char? does'nt it matter what kart you pick, not what char?
9. Is it my connection or does everyone usually have to do the "search for players" a mininum of 2 times?
10. If i press the "erase data" button does it erase my online record too?
11. when i search for "friends" it searches for people off my friend list, right?
12. when im searching for people and it finds a person is there a way to go? or do you have to wait?
13. when im searching for "friends" does it search for 4 or once it finds a friend it starts?
14. If i have some ones friend code but they dont have mine when i press search for friends will it still look for them? or since both of us dont have each other's friend codes we cant race together unless we meet each other randomly?

thanks in advance.