下列源代码段在IE 5.0中的解析结果如题52图所示，仔细阅读源代码和题52图，按要求完成后面各题。
VRML语言<／title><／head><body><h3>8.4 VRML简介<／h3><hr width=50％ align=left color=000000><pre><font size=2> VRML (Virtual Reality Modeling Language)是一种模型语言，是描述虚拟环境中场景的一种标准。它定义了三维应用中常用的语言描述，<br>并具有简单的行为特征描述功能。<／font><／pre> <／body> <／html> </p><p><img src="https://img.ixiawen.com/uploadfile/2017/0713/20170713101049828.jpg"></p><p>若将网页中的横线居中，如何修改源代码</p>
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<p>参考答案：<b></b></p><p><img src="https://img.ixiawen.com/uploadfile/2017/0713/20170713101049643.jpg"></p> </div>
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