Operating System (OS)
Assembler language

None of these
is usually the primary user interface
is a mnemonic form of machine language
requires fixed-format commands
is quite different from the SCL interpreter

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Operating System (OS)
A critical region is

a program segment that has not been proved bug-free
one which is enclosed by a pair of P and V operations on semaphores
none is the above
a program segment where shared resources are accessed
a program segment that often causes unexpected system crashes

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