按照食品添加剂使用卫生标准规定,不得用于馒头等漂白的食品添加剂是()
A.硫磺
B.BHA
C.亚硝酸盐
D.番茄红素
E.L-抗坏血酸硬脂酸酯
参考答案:A
—Will you stay for supper?
—Sorry, I _____. My mother is coming to see me. [ ]
A. mustn't
B. am not
C. needn't
D. won't
带电作业工具的机械试验标准是什么?