PART C

A. If (,,,,,) is a relation and

={,,,,,,,}

a set of set of functional dependencies, calculate the closure of {,} with respect to , i.e. {,}+.

3 Marks

B. Consider a relation (,,,,) with the following set of functional dependencies

={,,}

is {,} a candidate key of the relation ? If is not, is {,,} a candidate key of the relation ? Justify your answer.

6 Marks

C. The Cavendish Institute of Technology (CIT) is using forms to store module results; the table below shows the DB103 Databases module results.

Module Code:	DB103	Module Title:	Database Systems
Lecturer:	J Smith
Results_Date:	01-06-2022	No. students:	9
Student_id	Student_Name	Degree_Code	Mark	Result
116041	Bruno, K	BIS	81	Dist
121343	Jones, M	BIS	66	Merit
212323	James, B	Comp	67	Merit
133112	Patel, V	IS&T	32	Fail
200112	Partiss, R	BIS	88	Dist
114898	Richards, X	IS&T	62	Pass
100656	Smith, B	Comb. Sc	71	Merit
197002	Tomba, Q	BIS	59	Pass
161700	Olabumni, A	Comp	51	Pass
Mean	64.1
Standard Deviation	15.4