Consider the following relation: Articles (ID, title, journal, issue, year, startpage, endpage, TR_ID) It contains information on articles published in scientific journals. Each article has a unique ID, a title and information on the journal where it got published (name of journal, issue number, year and pages). Also, if results of an article is previously published in an internal paper known as a 'technical report' (TR), the id of this technical report can be specified. The following is an instance of the relation. Answer the following questions based on the above relation. a) How can 'deletion anomalies' occur in relation Articles? Explain with an example. b) What is the primary key of Articles relation? c) Perform normalization into BCNF over the given relation and state the resulting relations. Justify the steps you have taken in detail