A:are going to spend
B:aren't going to spend
C:spent
D:didn't spend
西气东输二线工程西起新疆霍尔果斯口岸,南至广州,东至上海,途经14个省(区市)。
满足条件a=4,b=32,A=45°的△ABC的个数是( )
火药开始运用于军事是在北宋末年。( )