Introduce specialization/generalization concepts into the ER model shown in Figure 13.11 and described in Exercise 12.13 to show the following:
(a) The majority of parking spaces are under cover and each can be allocated for use by a
member of staff for a monthly rate.
(b) Parking spaces that are not under cover are free to use and each can be allocated for use
by a member of staff.
(c) Up to twenty covered parking spaces are available for use by visitors to the company.
However, only members of staff are able to book out a space for the day of the visit. There is no charge for this type of booking, but the member of staff must provide the visitor’s vehicle
license number.
This figure takes the original Figure 13.11 and adds the additional requirements described
above (a) to (c) using enhanced EER concepts.
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Answer the following statements true (T) or false (F)
1. MS-DOS views the data stored in a disk file as a series of records. 2. The Intel processor at the heart of most MS-DOS systems relies on interrupts to establish communication with its peripheral devices. 3. The key to MS-DOS interrupt processing is an interrupt vector table that occupies the first 1K bytes of memory. 4. Under MS-DOS, the addresses of interrupt handler routines are listed in an interrupt vector table.
Copyleft is a policy
a. that protects you from having others use your work. b. to legalize unlimited copying of digital music. c. is a term for a set of licensing plans. d. all of the above
Biometric objects are entirely foolproof.
Answer the following statement true (T) or false (F)
A processor contains small, high-speed storage locations, called ______, that temporarily hold data and instructions.
Fill in the blank(s) with the appropriate word(s).