# Introduction This challenge includes background information about Chinese Taoism that might hinder understanding of the topic. Please grasp the objective with examples. In this challenge, we will fix the code provided by great master Tom for calculating the zero emissions index of a new home. The code is divided into two parts: `NumberAdd.java` and `StaticField.java`. Our task is to correct the code and make it meet the specified requirements. We are not allowed to modify the file names, class names, method definitions, and method names. Once we have made the necessary corrections, we can test and verify the challenge result.
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