8. How many 4-digit numbers begin with an odd digit and end with an even digit?
A.250 B.500 C.2，000 D.2.500 E.5.000
9.answer： A
10. In a bowl that contains 20 marbles， 7 are green， 6 are red， and theremainder are blue. Two marbles are to be drawn at random from the bowl withoutreplacement.
Column A： The probability that one marble is green and the other marble isred.
