. .What you said just now ________me of that American professor. A. mentioned B. informed C. reminded D. memorized
,从CO2来看是__________反应,从C来看,是__________反应。
图中R1=4Ω,R2=9Ω,R3=18Ω。通电后 ( ) A.经R1和R3的电流之比I
定义在R上函数f(x)满足f(0)= 0,f(x)+ f(1-x)=1,且 当时,,则( ) A. B. C.
如图a,△ABC和△CEF是两个大小不等的等边三角形(等边三角形为三条边相等,三个角为60°的三角形),且有一个公共顶点C,点F、B、C在同一直线上,
How was the weather yesterday? Oh, It was terrible. It rained ____ heavily____ few people could go out. A. such ,that B. very, that C. too ,to D. so, that
下列属于人类遗传病的是( ) A.坏血病 B.艾滋病 C.白化病 D.巨人症
设NA表示阿伏加得德罗常数的数值,下列叙述中正确的是( )A.标准状况下,22.4LH2O中所含有的氢原子数为2NA B.常温常压下,22 .4 L氧气所含的