A:高锰酸钾溶液
B:溴化钾溶液
C:溴水
D:硝酸银溶液
下列物质中,与钠、氢氧化钠溶液、小苏打溶液均能发生化学反应的是( )
读世界某海区洋流分布示意图(图),完成下列各题.
A.What about my toy bear?
B.Is it on your bed?
C.No, it isn't.
Alice:Mum,where is my car? Is it in the toy box?
Mum:____ It's in the desk.
Alice:Oh,thanks.____
Mum:____
Alice:Oh,yes,it is.
用数学归纳法证明不等式1+ 123 + 133 +…+ 1n3 <2﹣ 1n (n≥2,n∈N+)时,第一步应验证不等式( )