A:等腰三角形
B:直角三角形
C:等腰直角三角形
D:等腰三角形或直角三角形
依次填入下面一段文字横线处的语句,衔接最恰当的一组是( )在我国古代,人们盛物用的器皿除陶器等之外,还有一种容器,是葫芦。________,________。______。________,________。________。①最早的记载见于《诗经》,如《公刘》篇中“酌之用匏”的“匏”就是指葫芦②用葫芦做容器是先民们认识自然、利用自然的结果③葫芦是一种葫芦科爬藤植物的果实④葫芦成熟后,掏空里面的籽瓤,即可当容器使用⑤它大多呈哑铃状,上面小下面大⑥我国劳动人民使用葫芦盛物的历史非常悠久
阅读下列短文,从每小题的三个选项中选出最佳答案
It is morning now. Look at the sun, it rises in the east(东方). Look at the tree, the shadow is long. It is noon now. The sun is high in the sky. It is very hot. Look at the tree. The shadow is short. It is evening now. The sun goes down in the west(西方). Look at the tree, the shadow is long again. It is night now. The moon is high in the sky. There are some stars in the sky too.
①2H2O2═2H2O+O2↑
②2Na2 O2+2H20═4NaOH十O2↑
③2Na2O2+2CO2═2Na2CO3+O2
④2CaO2+2H2O═2Ca(OH)2+O2↑
⑤2CaO2+2CO2═2CaCO3↓+O2
⑥KClO3不与H2O,CO2反应
在鱼苗长途运输中你认为最适合加入的物质是( )