A:−BC→+12BA→
B:−BC→−12BA→
C:BC→−12BA→
D:BC→+12BA→
唐朝由盛到衰的转折点是( )
我国某校地理兴趣小组的同学,把世界上四地年内正午太阳高度变化及方向绘成简图(如下)。读图,回答:当②地正午太阳高度达到最大值时
He won in the story competition and his parents were very .