A:“两弹一星”成果是在②时期取得的
B:“文革”使④时期内没有取得科技成就
C:“一五”计划促进了①时期的科技发展
D:籼型杂交水稻是在⑤时期取得的成果
完形填空
Look! There 1many kites in the2.They are red,yellow and blue.I like 3kites 4 much.But I can't fly very5.My brother Peter can do6 well.He often 7me fly kites.We go out8our kites every Sunday.9my brother's help,now I can fly10.
①X+Z(NO3)2=X(NO3)2+Z ②X+YSO4=XSO4+Y ③Z+YSO4=ZSO4+Y
则这三种金属的活动性由强到弱的顺序是( )