设a是含有n个分量的整数数组,写出求n个整数之和的递归定义_______,写出求n个整数之积的递归定义______

If the absolute refractory period of a cell is 2 ms, ho...

单项选择题If the absolute refractory period of a cell is 2 ms, how many action potentials it could fire in one senond?

iPhone4为用户提供了更长的电池使用时间，在3G网络中的通话时间长达（）小时。

未知题型iPhone4为用户提供了更长的电池使用时间，在3G网络中的通话时间长达（）小时。

Jimi sold a machine which originally cost $14,900. At t...

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A、Profit of $1,485
B、Loss of $1,485
C、Loss of $1,495
D、Profit of $1,495