右图所示某分子的部分结构图，据图分析下列说法最准确的是 （ ） A．圈中共有4种核苷酸，会在转录过程中出现 B．图中共有
molCO和1molCO2具有相同的：①分子数 ②原子总数 ③碳原子数 ④氧原子数 A．①③ B．②④ C．①④
She thought herself_______ to her friends because her family was rich. A. higher B. better C. richer D. superior
在中国作家魏巍的笔下，它是“地球的红飘带”；在美国作家素尔兹·伯里的笔下，它是“前所未有”的事；在美国记者埃德加·斯诺的笔下，它是惊心
Although it seemed to be _____ painful experience, he still found it ____ fun. A. a, / B. /, a C. a, the D. a, a
Baby sign language is a growing movement.Pointing to a colorful flower, Tricia Campbell lifts her baby's soft hand, and rapidly moves it from one side of his nose to the other as she sniffs (嗅) l
下列说法正确的是（ ）A：若2x=3，则x=6 B：若x=6，则x=12 C：若a＋b=0,则a=b D:若－12x=144，则x=12
已知|a|=2，|b|=，a与b的夹角为45°，要使λb-a与a垂直，则λ=_______________.
