Verify Answers of Common Sense Test

Here is the TEST! 

Answer 1: If you answered that you are first, then you are absolutely wrong! If you overtake the second person and you take his place, you are second!
 
Answer 2: If you answered that you are second to last, then you are wrong again. Tell me, how can you overtake the LAST person!
 
Answer 3: Did you get 5000? The correct answer is actually 4100.
Don't believe it? Check with your calculator! Today is definitely not your day. Maybe you will get the last question right?

Answer 4: Tunu?
NO! Of course not. Her name is Mary. Read the question again.

Bonus Answer : He just has to open his mouth and ask, so simple