——Did you go to Jufeng Temple ___ the Peach Blossom Festival(桃花节)?——Yes. The flowers were beautiful and bees were flying ____ them.
A:during, among
B:during, between
C:through, among
D:through, between
要使视野中单个细胞最大,你认为应选用的显微镜镜头组合是( )
(Ⅰ)求第一轮闯关成功的概率;
(Ⅱ)如果第i轮闯关成功所获的奖金数f(i)=10000× 12i (单位:元),求某人闯关获得奖金不超过1250元的概率;
(Ⅲ)如果游戏只进行到第四轮,第四轮后不论游戏成功与否,都终止游戏,记进行的轮数为随机变量X,求x的分布列和数学期望.
ClSO3H称为氯磺酸,是﹣种强酸.对于反应:ClSO3H+HCOOH═CO+HCl+H2SO4有如下判断,其中合理的是( )