生产经营单位必须为从业人员提供符合国家标准或者行业标准的(),并监督、教育从业人员按照使用规则佩戴、使用。
A.劳动工具
B.劳动防护工具
C.劳动保护
D.劳动设备
参考答案:B
下列表示对应化学反应的离子方程式正确的是 ( )
A.向银氨溶液中滴加乙醛:
CH3CHO +2[Ag(NH3)2]+ + H2OCH3COO- + NH4+ +3NH3 + 2Ag↓+2H+
B.苯酚钠溶液中通入少量CO2:
C.硫酸氢铵溶液中滴加少量NaOH溶液:H++NH4++2OH-=NH3·H2O+H2O
D.氯乙酸与足量的氢氧化钠溶液共热:CH2ClCOOH+OH—△CH2ClCOO—+H2O
Sometimes a few words of _____ from his teacher to the one who has just failed in the exam may encourage
him to stand up. [ ]
A. compromise
B. confidence
C. comfort
D. consultant