HOTSPOT
You are reviewing the following class that is used to manage the results of a 5K race:
For each of the following statements, select Yes if the statement is true. Otherwise, select
No. Each correct selection is worth one point.
Answer: 
Explanation:
there wil be a chance he will trow an exeception.
Only when _name = null;
so it should be no
1 – YES. You can set player’s ranking only calling MatchName method. If you trying to add another score for the same player name method will skip in line return.
2 – NO. I don’t see any exceptions. Correct me if I’m wrong.
3 – NO. You can’t change constant properties like Key.
I think it would throw an exception on 2. The _name property isn’t set anywhere and if you call ToLower() on a null property you’ll get the NullReferenceException.