A:空气是混合物——空气由不同种分子构成
B:缉毒犬能根据气味发现毒品,是因为分子在不断运动
C:水电解生成氢气和氧气,是因为分子在化学变化中可以改变
D:10mL酒精和10mL水混合后体积小于20mL.是因为分子变小了
Hello, boys and girls. I'm Danny. I'm tall. I'm fat. I can draw my teacher. Look, this is my teacher. He's a new teacher. He's Mr Wang. He's tall. He is big. He can play football and swim. He can ride a bicycle, too. Look at the bicycle. It's not red. It's green. It's new. I like his bicycle. Can you ride a bicycle?
如图表示人体血液流经血管a、b、c时,血液含氧量与血压的变化,下列有关叙述正确的是( )