看图,配对,将句子编号写在相应的横线上。
A. The pears are juicy and sweet. Here you are.
B. - How is the juice? - It's very sweet.
C. Smell the soup. It's very nice.
D. - How is the rice, Peter? - It's yummy.
① ____
② ____
③ ____
④ ____
DNA…-A-T-G-C-G-C-…
RNA…-U-A-C-G-C-G-…
﹣2的绝对值是( )
在298 K、100 kPa时,已知:2H2O(g)===2H2(g)+O2(g) H1 Cl2(g)+2H2(g)===2HCl(g) H2 2Cl2(g)+ 2H2O(g)===4HCl(g)+O2(g) H3则H3与H2和H1之间的关系正确的是( )