Page 1 of 8 Marking guide for COMPUTER SCIENCE EVALUATION PAPER II FOR S6MCE 2020 /120 marks SECTION A: ATTEMPT ALL QUESTIONS (50 MARKS) 1. Explain the following terms: 5 Marks a. Artificial intelligence is ability of a computer to mimic a human being behavior. (1 mark) b. Pointer is a variable that stores/points the address of another variable. (1 mark) c. Microprocessor is the brain of a computer (1 mark) d. DHCP is short for Dynamic Host Configuration Protocol. Its main task is to automatically assign an IP address to devices across the network. It first checks for the next available address not yet taken by any device, then assigns this to a network device. (1 mark) e. Firewire is external port, similar to a USB port, that provides a high data transmission rate (1 mark) 2. Categorize followings device according to their transmission modes. /2 marks a. Radio: simplex b. Walkie–Talkie: half- duplex c. Phone: Full duplex d. Computer: Full duplex 3. Distinguish Bandwidth to latency /2 marks Bandwidth is the amount of data that can be transmitted in a fixed amount of time. Latency is the time between requesting data and receiving data. 4. Which of the following are layers in the TCP/IP model? /1 mark a) Application b) Session c) Transport d) Intranet e) Data Link f) Physical 5. Name the following parts of a computer /3 Marks 1) AC power port 2) Ethernet port 3) VGA port 4) Ventilation 5) HDMI port 6) USB ports 6. State two reasons that make use powder-based fire extinguishers in computer lab is unsuitable. /2 Marks a) Powder may increase friction between mechanical parts. (1 mark) b) Powder may weaken or damage some materials in computer lab. (1 mark) 7. Differentiate the following terms /4 marks a. System software and application software.
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Marking guide for COMPUTER SCIENCE EVALUATION PAPER II FOR S6MCE 2020 /120 marks
SECTION A: ATTEMPT ALL QUESTIONS (50 MARKS)
1. Explain the following terms: 5 Marks
a. Artificial intelligence is ability of a computer to mimic a human being behavior. (1 mark)
b. Pointer is a variable that stores/points the address of another variable. (1 mark) c. Microprocessor is the brain of a computer (1 mark)
d. DHCP is short for Dynamic Host Configuration Protocol. Its main task is to automatically assign an IP address to devices across the network. It first checks for the next available address not yet taken by any device, then assigns this to a network device. (1 mark)
e. Firewire is external port, similar to a USB port, that provides a high data transmission rate (1 mark)
2. Categorize followings device according to their transmission modes. /2 marks
a. Radio: simplex
b. Walkie–Talkie: half- duplex
c. Phone: Full duplex
d. Computer: Full duplex
3. Distinguish Bandwidth to latency /2 marks
Bandwidth is the amount of data that can be transmitted in a fixed amount of time.
Latency is the time between requesting data and receiving data.
4. Which of the following are layers in the TCP/IP model? /1 mark
a) Application
b) Session
c) Transport
d) Intranet
e) Data Link
f) Physical
5. Name the following parts of a computer /3 Marks
1) AC power port
2) Ethernet port
3) VGA port
4) Ventilation
5) HDMI port
6) USB ports
6. State two reasons that make use powder-based fire extinguishers in computer lab is unsuitable. /2 Marks
a) Powder may increase friction between mechanical parts. (1 mark)
b) Powder may weaken or damage some materials in computer lab. (1 mark)
7. Differentiate the following terms /4 marks
a. System software and application software.
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System software is software that makes possible the system to run and perform useful work to the user while
applications software are programs that work with operating system to help the users to do specific types of
tasks or works.
b. Physical threat to logical threat. / 2 marks
Physical threats are digital storage media and hardware that can damage or destroy the computer system while
logical threats are events or attacks that remove, corrupt, deny access, or steal information.
c. computer to computer science
Computer is an electronic device capable of receiving raw facts (data) and performing a sequence of
operations on the data based on special computer instructions (processing) to produce desired output
(information) while Computer science is a branch of science that deals with theory of computation, or design
and operation of computer hardware and software and the application of computers in all sectors.
8. Evaluate the following: 5 marks a. Subtract (11110.1101)2 from (111111.1111)2 (1 mark)
𝟏𝟏𝟏𝟏𝟏𝟏.𝟏𝟏𝟏𝟏−𝟏𝟏𝟏𝟏𝟎.𝟏𝟏𝟎𝟏
𝟏𝟎𝟎𝟎𝟎𝟏.𝟎𝟎𝟏𝟎
b. Find binary equivalent of (251.35)10=(?)2 1 (2marks)
BOOKS BookId BookTitle BorrowerId 10 Computer Science for Rwandan Schools Senior 4 112018 12 Data communications and Networking 112018 13 Fundamentals of Mathematics 122018 14 Production Economics: The Basic Theory of
Production Optimisation 132018
15 Encyclopedia of Mathematics 122018 i. What is primary key for each table and give reasons. ii. Identify the foreign key in the BOOKS table.
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iii. Identify the candidate keys in both tables. iv. Identify the relationship between BORROWERS and BOOKS tables and draw the E-R model. v. Does the BOOKS table exhibit referential integrity? Why or why not?
Answers i. Borrowerid, BookId are unique and stable (2 marks) ii. BorrowerId (1 mark) iii. BORROWERS candidate keys are: BookId,BookTitle BOOKS candidate keys are: BorrowerId, BorroweName-Assume that there is no borrowers having same name (2 marks ) iv. Relationship between BORROWERS and BOOKS is borrows. (1 marks)
ER Diagram (3 marks)
vi. Yes, table BOOKS exhibits referential integrity. Because BorrowerId appears in BOOKS entity is
foreign key from reference table BORROWERS. (1 mark) SECTION C: ATTEMPT ANY ONE QUESTION. (15 MARKS)
23. The government of Rwanda is helping students wishing transfer from SCHOOL A to SCHOOL B. The students must send their request to REB website using the form below. Write HTML code that display this form. (15 marks)
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<HTML>
<b><caption>BOARDING SCHOOL REQUEST FORM </caption><BR><BR></b>