肾病患者需要食用低钠盐的食品。目前，市场供应的低钠盐多为苹果酸钠盐（C4H5O5Na）。每日食用6 g苹果酸钠盐，人体摄入的钠元素质量与等量食盐中钠元素质量之比为（ ）
A．6:5
B．71:266
C．104:39
D．39:104
D
题目分析：6g食盐中的钠元素为：6g×
；6g低钠盐中钠元素的质量为6g×
，故钠元素的质量比为39:104，故答案选择D
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| In England,people often talk about the l because they can experience four seasons (季节) in one 2 . In the morning the weather is warm like in spring (春天). An hour later black clouds come, and then it 3 hard. In the afternoon the sky will be clear, the sun will begin to shine, and it will be 4 at this time of day. In England, you can 5 have summer in winter, or have winter in summer. So in winter you can 6 sometimes and in summer you should take 7 clothes with you. When you go to England, you'll see that some 8 people usually take an umbrella or a raincoat with them on a 9 day, but you should not laugh at them.If you don't take an umbrella or a 10 , you'll regret (遗憾) later in England. | ||||
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