Computer Languages Questions and Answers

Answer: C

Correct answer: if then else statement

Two possible actions need two branches, and the ELSE clause is what supplies the second. An if then statement has one branch and does nothing when the condition fails.

Answer: A

Correct answer: Rise time

Rise time is defined as the interval in which a pulse climbs from 10 per cent to 90 per cent of its final value; the 10 and 90 per cent marks are used because the very beginning and end of the transition are hard to identify. Decay time is the corresponding measure for the fall.

Answer: C

Correct answer: LISP

LISP, created by John McCarthy in 1958, is built on list processing and treats code and data in the same form, which suits symbolic manipulation. FORTRAN was written for scientific computation and COBOL for business data processing.

Answer: C

Correct answer: All of the above

A problem oriented language lets the programmer state the problem in the terms of the application rather than in the terms of the machine. Both BASIC and PL/1 are high level languages of that kind.

Answer: C

Correct answer: It uses alphabetic codes.

Assembly language replaces the binary operation codes of machine language with short mnemonics - ADD, MOV, JMP - which is what makes it readable. It still has to be translated, by an assembler, and it is harder to write in than any high level language, so the other statements are false.

Answer: C

Correct answer: 8 bits

The data path is the number of bits the processor moves at once, and in the eight-bit microprocessors these questions are written around - the 8080, the 6502, the Z-80 - that width is one byte. Later families widened it to 16, 32 and 64 bits.

Answer: A

Correct answer: -1

A rogue value is a value outside the range of the real data, used to signal the end of input. Marks cannot be negative, so -1 can never be mistaken for a mark, which is precisely what makes it a safe terminator.

Answer: B

Correct answer: real numbers

In programming, real is the type that admits a fractional part, as against integer, which does not. Prime and composite are properties of integers rather than data types.

Answer: A

Correct answer: selection

The three constructs of structured programming come in order: sequence first, then selection - choosing between alternatives - and then repetition. Selection is what allows an algorithm to do more than one fixed thing.

Answer: B

Correct answer: procedure

Structured programming works by stepwise refinement: each operation is broken into smaller operations, and in Pascal each is written as a procedure. The other options describe properties of data, not the means of refining an operation.