这个复杂的数学计算花了我们整整一上午的时间。

The complex mathematical ___calculation took us the whole morning to complete.

他的成功并非偶然，而是精心计算的结果。

His success was not by chance, but the result of careful ___calculation.

计算结果显示我们需要至少五天的准备时间。

The ___calculation shows we need at least five days to prepare.