(b) The incomplete XML document shown below is intended to mark-up data relating to a CD catalogue. The XML expresses the fact that the singer ED Sheeran released the CD Equals in 2021. (i) Assuming that the document has been completed with appropriate replacement for the ellipses (...), state whether the document is well-formed XML. Describe any flaws in the XML document design that are evident in the above sample and rewrite the sample using XML that overcomes these flaws. (ii) Write a document type definition (DTD) for validating documents of the format you designed for part (i) of this question.