A:63
B:23
C:52
D:214
图中O为极点,OA、OB为经线,A、B分别为晨线和昏线与4O°N的交点。据此回答题。
—Why are you so tired?
—Well, I have _______ housework to do on weekends.
“一战”爆发后,意大利反而参加到协约国一方作战,主要是因为( )