Updating a tag in XHTML

WordDocument_doc.xhtml

I have an xhtml file(see the attached one) and i want to update
img src="/d/WordDocument_doc_parts/image0.jpg"  to
img src="http://localhost:8016/d/WordDocument_doc_parts/image0.jpg"
Is there any way to do this  either using XQuery or using C#. Any reply regarding this would be of great help.

thanking you in advance,
Sabira