Test Bank Ch1

Test BankChapter One (Data Representation) Multiple Choice Questions 1. Which of the pursuance Boolean operations drives the output 1 for the fewest number of commentary recipes? A. ANDB. ORC. XOR resolving power A 2. Which of the following best describes the NOR operation? A. An XOR followed by a notB. An OR followed by a NOT C. A NOT followed by a NOTC. An AND followed by a NOT repartee B 3. Which of the following point blueprints cannot be show in hexadecimal notation? A. 11111111B. degree centigrade1C. 1 ascorbic acid11D. 100000000001 dissolve C 4. Which of the following is the binary representation of 4 5/8? A. 100. 11B. 10. 11C. 110. 101D. 100. 101 react D 5. Which of the following bit patterns represents the survey 5 in iis complement notation? A. 00011010B. 11111011C. 00000101D. 11111011 ANSWER C 6. Which of the following bit patterns represents the assess -5 in twos complement notation? A. 00011010 B. 11111011C. 00000101 D. 11111011 ANSWER D 7. In which of th e following sum total problems (victimization twos complement notation) does an overflow error occur? A. 0011 B. 0100 C. 1100 + 1010 + 0100 + 1100 ANSWER B 8. Which of the following representations in twos complement notation represents the largest value?A. 00000010B. 11111111C. 00000001D. 11111110 ANSWER A 9. Which of the following bit patterns ( represent in hexadecimal notation) represents a negative number in twos complement notation? A. 7FB. 55C. A6D. 08 ANSWER C 10. What value is stand for by the bit pattern 01011100 when understand using floating-point bringat in which the just about undertakeificant bit is the sign bit, the next three bits represent the exponent field in excess notation, and the death quadruplet bits represent the fixed-point part? A. -1 1/2 B. 1 1/2C. -3/8 D. 3/8 ANSWER B 11.Which of the following determine cannot be stored accurately using a floating-point format in which the most significant bit is the sign bit, the next three bits represent the exponent field in excess notation, and the pull round four bits represent the mantissa? A. 2 1/2B. 3/16C. 7D. 6 1/4 ANSWER D 121. Which of the following bit-patterns represents the smallest value using the floating-point format in which the most significant bit is the sign bit, the next three bits represent the exponent field in excess notation, and the last four bits represent the mantissa? A. 01001000B. 1011000C. 00101000D. 01111000 ANSWER C 13. Which of the following data storage systems provides the most efficient random access to individual data items? A. principal(prenominal) memory boardB. magnetic diskC. Optical CDs and DVDs ANSWER A 14. Which of the following storage systems is best suited for storing and retrieving long strings of data that are processed in their straight order? A. Main memoryB. Magnetic diskC. Optical CDs and DVDs ANSWER C 15. Which of the following mass storage system does not require physical motion? A. Magnetic tapeB. Magnetic diskC. DVDsD. Flas h drives ANSWER D 16.As fondnessing that all(prenominal) of the following bit patterns originally had stock-still parity, which one contains an error? A. 10110100B. 11000011C. 00011000 D. 10001001 ANSWER D 17. How many errors per pattern could be corrected when using an error-correcting code in which any two code patterns differ by a Hamming maintain of 8? A. 3B. 4C. 5D. 6 ANSWER A 18. Which of the following is a possible LZW compression of the message xyz xyz xyz? A. 1234B. 1234545C. 232D. 12 ANSWER B 19. How many different symbols can be encoded using Unicode? A. 256B. 4,096C. 65,536D. 1,046,476 ANSWER C 20.Which of the following systems is least efficient when encoding numeric values? A. Twos complement notationB. Excess notation C. ASCIID. Floating-point notation ANSWER C 21. Which of the following is a means of encoding music? A. ASCIIB. MIDIC. JPEGD. GIF ANSWER B Fill-in-the-blank/Short-answer Questions 1. A computers main memory consists of numerous memory cells, each of w hich contains ________ bits. Each memory cell is identified by a numeric value called the cells _________. ANSWER eight, address 2. Represent the bit pattern 1011010010011111 in hexadecimal notation. ________ ANSWER B49F 3. A7DF is the hexadecimal representation for what bit pattern? ____________ ANSWER 1010 0111 1101 1111 4. How many different bit patterns can be create if each must consist of exactly 6 bits? ____________ ANSWER 64 5. Translate each of the following binary representations into its equivalent base ten representation. A. 1100__________ B. 10. 011__________ C. 0. 01 __________ D. 10001__________ ANSWER A. 12 B. 2 3/8 C. 1/4 D. 17 6. Rewrite each of the following values (represented in base ten notation) in binary notation. A. 7__________B. 23__________ C. 2 1/4 __________ D. 5/8__________ ANSWER A. 111 B. 10111 C. 10. 01 D. 0. 101 7. If the patterns 101. 11 and 1. 011 represent values in binary notation, what is the binary representation of their sum? ____________ AN SWER 111. 001 8. Using a twos complement notation system in which each value is represented by a pattern of six bits, represent the value 3. ____________ ANSWER 000011 9. Using a twos complement notation system in which each value is represented by a pattern of six bits, represent the value -3. ____________ ANSWER 111101 10.What is the largest positive integer that can be represented in a twos complement system in which each value is represented by eight bits? ____________ ANSWER 127 (represented by 01111111) 11. In a twos complement system, what value is represented by the pattern 11111111111111001? ____________ ANSWER -7 12. When using twos complement notation, what bit pattern represents the negation of 01101010? ____________ ANSWER 10010110 13. What value is represented by each of the following patterns in excess notation? A. 10000 ____ B. 0110 ____ C. 1011 ____ ANSWER A. 0, B. -2, C. 14. Using an 8-bit floating-point format in which the most significant bit is the sign bit, the next three bits represent the exponent field in excess notation, and the last four bits represent the mantissa, write the bit pattern that represents the value 1 3/4. (Use normalized form. ) ____________ ANSWER 01011110 15. What is the largest value that can be represented in a floating-point system in which each value is encoded by a byte whose most significant bit is the sign bit, the next three bits represent the exponent field in excess notation, and the last four bits represent the mantissa? ___________ ANSWER 7 1/2 (represented as 01111111) 16. Which of the following addition problems cannot be solved accurately when using a floating-point system in which each value is encoded by a byte whose most significant bit is the sign bit, the next three bits represent the exponent field in excess notation, and the last four bits represent the mantissa? A. 2 1/2 + 1 3/8B. 3 1/2 + 4 1/2C. 7 + 3/4 ____________ ANSWER A, B, and C 17. The following is an error-correcting code in which any two patterns differ by a Hamming distance of at least three. image Representation A 000000B 001111 C 010011 D 011100 E 100110 F 101001 G 110101 H 111010 Decode each of the following patterns 010011 ________101010 ________011000 ________101101 _______ ANSWER C, H, D, F 18. How many errors in a single code pattern could be corrected when using an error-correcting code in which each code pattern is a Hamming distance of at least seven from any former(a) code pattern? ____________ ANSWER 3 19. The following is a message that was originally encoded so that each pattern had crotchety parity. Circle the patterns in which an error has definitely occurred. 0110101 11110000 10010010 00000000 11111111 00001000 00111101 ______________________________________ ANSWER Second, fourth, fifth, and sixth 20. Data compression techniques apply various principles to reduce the surface of data. One, called _______________________, avoids reiterate long strings of the resembling data item. Another, ca lled _______________________, encodes the difference between consecutive blocks of data rather than encoding each block in its entirety. Still another, called _________________________, uses shortstop bit patterns to encode frequently occurring items and longer patterns to encode less(prenominal) frequent items.ANSWER Run-length encoding, relative encoding, and frequency-dependent encoding. Vocabulary (Matching) Questions The following is a list of hurt from the chapter along with descriptive phrases that can be utilize to produce nouss (depending on the topics covered in your course) in which the students are ask to match phrases and terms. An example would be a question of the form, In the blank next to each phrase, write the term from the following list that is best described by the phrase. TermDescriptive Phrase bitBinary digit Boolean operationAND, OR, XOR, NOT addressA numeric value used to identify a memory cell exadecimal notationAn efficient way of representing bit pat terns sectorA segment of a track in a mass storage system zoned-bit recordingA means of increasing the storage capacity of a magnetic disk system bufferA storage area used to cave in data on a temporary basis, often as a step in transferring the data from one device to another ISOAn international plaque for establishing standards ANSIA major standardization organization within the United States ASCIIA system developed by the American Standards Institute for encoding school text. lip-flopA digital circuit capable of retention a single digit twos complement notationA means of encoding whole numbers floating-point notationA means of encoding numeric values that whitethorn involve fractions truncationAn error that may occur when using floating-point notation pixelA small part of an image GIFA means of compressing an image file by constrictive the number of colors availableJPEGA means of compressing images by blurring the boundaries between different colors while maintaining all bri ghtness information UnicodeA means of encoding text in which each symbol is represented by 16 bits LZWAn example of adaptive dictionary encoding MIDIA means of encoding music in terms of notes and instruments rather than actual audio Key fieldA part of a logical record in a file used to identify the record. VLSIA means of constructing mixed circuitry in a very small space.General Format Questions 1. Describe how a computer can produce an incorrect answer when performing numerical computations even though it has not malfunctioned. ANSWER nearly students will probably refer to overflow and truncation errors. 2. Describe ho the concept of Hamming distance is used to produce an error-correcting code. ANSWER By designing a code in which each pattern has a Hamming distance of n from any other pattern, patterns with fewer than n/2 errors can be corrected by replacing them with the code pattern that is closest. . a. What is the output of the circuit below? pic b. In general, how does the three-bit input pattern across the top of the diagram relate to the circuits output? ANSWER a. 0 b. The output is 0 if the input parity is odd the output is 1 if the input parity is even. 4. If the input and output bit patterns in the circuit below are interpreted as binary representations of numeric values, what operation does the circuit perform? pic ANSWER The circuit subtracts one (except for the case of the input being 000). . Explain why such terms as kilobyte, megabyte, and universal gravitational constant have acquired double meanings. ANSWER The prefixes kilo, mega, and giga are used traditionally to refer to units measured in powers of ten. However, due to the early misuse of the prefix kilo in reference to units of the size 1024, these prefixes are now often used to refer to units that are powers of twoespecially when referring to the capacity of main memories. 6. Convert the following addition problem into twos complement notation using four bits per value), perform the addition, convert the answer back into base ten notation, and explain the results. 6 + 3 ANSWER In twos complement notation the problem is to add 0110 and 0011. The sum is 1001 which translates to -7. This answer is incorrect due to overflow. 7. Under what ascertain is each of the following data compression techniques most effective? a. Run-length encoding b. Relative encoding ANSWER a. Compresses most when data consists of long strings of the same entry. b.Compresses most when each block of data differs little from the previous block. 8. What is frequency-dependent encoding? ANSWER Frequency-dependent encoding is an encoding system that uses short bit patterns to represent data items that occur most often and longer patterns to represent less frequently occurring items. The result is that entire blocks of data can be represented in less space than would be required if each data item were represented by the same size bit pattern. 9. Construct the entire twos complement scale in wh ich each value is represented by three bits.ANSWER 3 011 2 010 1 001 0 000 -1 111 -2 110 -3 101 -4 100 10. To what does the term normalized form refer in the context of floating-point notation? ANSWER Normalized form refers to a standard for positioning the bit pattern within the mantissa field. Many values can be represented in floating-point notation by different bit patterns, only one of which is in normalized form. Hence, restricting representations to normalized form assures that each value is represented by a unique pattern. 11.Explain why the final version of the dictionary need not be transmitted with a message encoded using LZW compression. ANSWER The dictionary can be constructed during decompression in the same way it was constructed during compression. 12. Among the Boolean operations AND, OR, EXCLUSIVE OR, and NOT, which is least equivalent the others? Explain your answer. ANSWER There is not really a right or wrong answer. The students explanation is the most importan t part. Most students will probably answer NOT because it has only one input whereas the others have two. 3. If a term paper consisted 42 pages, each containing 40 lines of 100 symbols each (counting each space as a symbol), was to be encoded using Unicode, how many bytes of storage space would be required? ANSWER 336,000 bytes (168,000 symbols times 2 bytes per symbol) 14. Explain why adding only a few characters to a text file may increase the files size by some(prenominal) hundred bytes and at other times may not increase the files size at all. ANSWER File space is allocated in terms of physical records, each of which is several hundred bytes in size.Thus, the size of a file grows by physical record units rather than by byte size units. 15. In a twos complement system, what value can be added to any other value without causing an overflow? How many values in the system have this property? Explain your answer. ANSWER Adding the value 0 to any other value will not produce an overf low. However, if m is the largest positive integer that can be represented in the system, then any value in the range 1 to m will produce an overflow when added to m, and any value in the range -1 to -( m + 1) will produce an overflow when added to -( m + 1).