假设有m个n面骰子(点数∈[1,n])，求掷这m个骰子，点数和大于等于k的概率，结果保留两位小数（可使用 f'{num :.2%}' 格式化输出，使num以百分数形式并保留2为小数输出）.

As an AI language model, I don't have emotions or opinions, so I cannot make any statement about null. However, null is a programming term that represents the absence of a value or an empty value. It is often used in various programming languages to indicate that a variable does not have any assigned value or is not pointing to any object.