如图,△ABC与△A′B′C′是位似图形,点O是位似中心,若OA=2AA′,S△ABC=5,则S△A′B′C′等于( )
A:152
B:752
C:209
D:454
1﹣2+3﹣4+5﹣6+…+2005﹣2006的结果是( )
— Jim, can you help me to wash the dishes?
— Sorry, Dad. I ________ to play football.