Scientis say that the Mars-500 test will take about 520 days______they

Scientis say that the Mars-500 test will take about 520 days______they
(1)-Scientis say that the Mars-500 test will take about 520 days______they perform the task during the real mission
-Good luck.I hope it goes well.
A.after B.before C.since D.as
(2)-I can't believe that______a little pet can eat______much food
-Yes,it's so amazing.
A.such;such B.so;so C.such;so D.so;such
(3)-Facing the global financial crisis,how do you deal with your money?
-___________________________.
A.Don't put all your eggs in one basket B.Many hands make light work.
C.Every dog has its day D.It's better to be safe than sorry
(4)-I made a lot of mistakes in the Maths exam.I'm afraid I didn't pass it.
-_________It can't be that bad.
A.Be careful B.Never mind C.Don't mention it D.Cheer up