object_name instance

dim object_name

dim name as object
like we want to an intiger then we write
dim a as integer.

There are two types of file systems ntfs and fat
ntfs is used for secutity encription and for sharing of 
space.

there is 3 type of file system in Windows operating 
systems. FAT, FAT32 & NTFS. NTFS having file/folder level 
security and parition limit is more.

• File Allocation Table (FAT)
 
• NTFS
 
• Universal Disk Format (UDF)

FAT(File Allocation Table)
FAT16: It is available in win95
FAT32 : It is available in win98,winXP,Win Me
NTFS (New Technology File System): It is available in Win 
NT3.5, Win NT 4.0, Win Nt 5.0, Win XP, Win2000, Win2K3

NTFS - you can assign disk quota
     -  file level permission, encryption and decryption

fat does not have

High Sierra
    ISO 9660
    Joliet
    UDF (Universal Disk Format)
    Mac HFS (Hierarchical File Format) not for windows 
    Rock Ridge
    Mount Rainier
    Ntfs
    Fat

32 bit application can run 32 bit processor .64 bit 
application can run 64 bit processor.also 64 bit can run on 
32 bit processor.

bit is a lenght of the data, if it is 32 or 64 bit 
application, to run this application hardware  should have 
the capacity to support this much of data bit.

The capacity of microprocessor  to process the data at a 
time determines the bit lengh of  application software.

semaphore uses one thread .so it can access little slower 
than ordinary variable.

Semaphore variable is used under 'n' process solutions to
handshake mutual exclusion rule, where as ordinary variable
is used such circumstance is error prone if set that
variable as boolean type even you get problem while setting
value to parent thread.

where n>1 

check it out!

4.None of the above

3)time sharing

2)security

virtual memory

time sharing

Critical Section comes in single process environment they
didn't share accross process boundary.

In C if you wish to implement criticalsection you have to
use windows datastructure CRITICAL_SECTION and create a
object to access its members.

Initialize it
  InitializeCriticalSection(&cs);
------------
-----------
function to call();
------------
DeleteCriticalSection(&cs);
.
.
call()
{
}

Now sure what is asked but anyway:
1. If the question is how would you implement critical 
section mechanism then the answer is to use a mutex.
2. If the question is to show how to use the critical 
section then the following code fragment adresses that:
//
//  Global variable or a member of some
//  dynamically allocated structure, usualy within
//  the data access to which it is protecting.
//
CRITICAL_SECTION cs;

VOID Init(VOID) {
   InitializeCriticalSection( &cs );
}

VOID SomeCall(VOID) {
  EnterCriticalSection( &cs );
  //
  //  Thread-safe block of code protected by critical 
section.
  //
  LeaveCriticalSection( &cs );
}

VOID
UnInit(VOID) {
  DeleteCriticalSection( &cs );
}

Semaphores are used to make system free from conflicts and 
hang. when more than one program are executed 
simultaniously then computer hangs and sometimes gives 
wrong output so instead to come out from this situation 
semaphore is used which takes care for program execution 
and manages it.

In computer programming, a mutex (mutual exclusion object)
is a program object that is created so that multiple program
thread can take turns sharing the same resource, such as
access to a file. Typically, when a program is started, it
creates a mutex for a given resource at the beginning by
requesting it from the system and the system returns a
unique name or ID for it. After that, any thread needing the
resource must use the mutex to lock the resource from other
threads while it is using the resource. If the mutex is
already locked, a thread needing the resource is typically
queued by the system and then given control when the mutex
becomes unlocked (when once more, the mutex is locked during
the new thread's use of the resource).

Named Objects. A name may be associated with any primitive, 
aggregate, ... An object thus named may then be 
instantiated (with possible additional ...