C51中数据类型sbit和bit的区别在于（）。
参考答案：bit用于定义位变量，不能定义位指针也不能定义位数组，位地址可变；sbit用于定义片内可位寻址位
Although we haven't got accurate statistics, it is estimated that ______ 300 factories in this province
closed down during the economic crisis.[ ]
A. finally
B. previously
C. obviously
D. approximately
核心价值观不分贫富、不分贵贱、不分政党派别、不分宗教信仰，所有公民都能平等的使用和消费。
