from 17 to 21

17. For an 80486 descriptor that contains a base address of 01000000H, a limit of OFFFFH, and G = 0, what starting and ending locations are addressed by this descriptor? 18. For a Pentium 4 descriptor that contains a base address of 00280000H, a limit of 00010H, and G = 1, what starting and ending locations are addressed by this descriptor? 19. If the DS register contains 0020H in a protected mode system, which global descriptor table entry is accessed? 20. Code a descriptor that describes a memory segment that begins at location 210000H and ends at location 21001FH. This memory segment is a code segment that can be read. The descriptor is for an 80286 microprocessor. 21. Code a descriptor that describes a memory segment that begins at location 03000000H and ends at location 05FFFFFFH. This memory segment is a data segment that grows upward in the memory system and can be written. The descriptor is for an 80386 microprocessor