有40个数据,其中最大值为45,最小值为12,若取组距为5对数据进行分组,则应分为( )
(____) I'm looking out of the window.
(____) Some children are making a snowman.
(____) In this photo,we are in the mountains.
(____) The wind is blowing and the sun is shining.
(____) I am having a lovely time.
如图是制作人体口腔上皮细胞临时玻片标本的过程,其正确顺序为( )
X溶液
Y溶液
①
CuCl2溶液和HCl溶液
NaOH溶液
②
Na2SO4溶液和H2SO4溶液
BaCl2溶液
③
NaCl溶液和HCl溶液
NaHCO3溶液
④
Na2CO3溶液和NaOH溶液
H2SO4溶液
( )