(R ? ?T) • (D ? T) $\frac { \sim \mathrm { T } \vee \mathrm { T } } { \sim \mathrm { R } \vee \sim \mathrm { D } }$

question 245

Multiple Choice

(R ? ?T) • (D ? T) $\frac { \sim \mathrm { T } \vee \mathrm { T } } { \sim \mathrm { R } \vee \sim \mathrm { D } }$

• A) MT-valid.
• B) CD-invalid.
• C) CD-valid.
• D) HS-valid.
• E) DD-valid.

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Definitions:

Collection Of Characters

A term that typically refers to a string or a set of letters, numbers, and other symbols considered as a single entity in computing.

Operator

In programming, a symbol that represents an operation (like addition or comparison) performed on one or more operands.

Aggregate Function

A function in computing that performs a calculation on a set of values and returns a single value, often used in database queries.

Average Amount

The result obtained by adding several quantities together and then dividing this total by the number of quantities.