—If I were you, I ______ for it last night instead of watching movies.
A:would prepare
B:prepared
C:had prepared
D:would have prepared
若方程组3x+2y=m+14x+3y=m-1的解满足x>y,则m的取值范围是 ( )
化学与生产、生活密切相关,请回答下列问题(填序号)
A.塑料 B.食盐 C.牛奶 D.硝酸铵 E.氯化钾
(1)富含蛋白质的物质是____ ;
(2)农作物生长需要的氮肥是____ ;
(3)属于有机合成材料的是 ____ .
计算:(2)解方程: