A:c(H+)>c(OH﹣)
B:c(CH3COO﹣)+c(CH3COOH)=0.2 mol•L﹣1
C:c(CH3COOH)>c(CH3COO﹣)
D:c(CH3COO﹣)+c(OH﹣)=0.1 mol•L﹣1
在矩形ABCD中,AB=5,AD=12,将矩形ABCD沿直线l向右翻滚两次至如图所示位置,则点B所经过的路线长是____ (结果不取近似值).
小明从家出发走了1.5时,每时走4.5千米.
把正确答语前的字母填到横线上
①6How many birds do you see?____
②I'd like car 18,please.____
③What's this?____
④How many balls do you have?____
a. I have 11. b. OK c. My new crayons d. I see 15.
化简:8=____
一个六棱柱的顶点个数、棱的条数、面的个数分别是( )