Statement evaluation. Specify whether each statement below is (i) always true, (ii) sometimes true, or (iii) never true. For those that are (ii) sometimes true, explain when the statement is true.

a. A context diagram does not include data stores.

b. A database table in 2NF is in 3NF as well.

c. A salesperson is an external entity in a data flow diagram.

d. Data flow diagrams are better than flowcharts for documenting accounting information systems.

e. Database forms can be used to look up information in a table.

f. Database queries store instructions, not data.

g. Database tables are needed for processes, external entities, and data stores in a DFD.

h. Database tables in 3NF are, by definition, also in 1NF and 2NF.

i. Decomposing a process numbered 2.0 would lead to numbers like 2.1, 2.2, and so on.

j. Lines in a data flow diagram should be labeled with verb phrases to show the movement of data.

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a sometimes true Context diagrams are used to provide a highlevel overview of a system They show the relationships between the different elements in a system but dont provide much detail about individ... View the full answer