2021 BVSS Computing P1 Solutions

1 Marking Scheme Q1 1(a) 1 mark for each correct line. Maximum 4 lines. Description Stage Gather requirements Train users to use the program. Plan solutions Compare the actual output with expected output. Write code Determine the complete set of outputs that is necessary to solve the problem. Test and refine code Write possible algorithms using either flowcharts or pseudo-code. Implement code 1(b) Description • An array is a variable with list of items of the same type that can be indexed. Example • For example, an array can be used to store 40 students’ marks. A repetition / loop can be used to process the array of 40 marks and this makes the program code more concise.

2 Q2 2(a) (i) • Data transfer is typically faster. • Data transfer is typically more secure. (ii) • Users can be connected to a wireless network as long as they are within range of the network coverage. • Low in cost • Easy to configure and manage. 2(b) Network Device Description Network interface card (NIC) NIC provides the hardware interface to enable the transfer of data between a device and a network. Network hub A device that transmits received packets to all connected device. Network bridge A device that constructs a single network by connecting two similar networks together. Router A device that forwards packets between separate networks. Modem A device that is responsible for modulation and demodulation. Wireless Access Point A device that allows other wireless devices to connect to a wired network.

3 Q3 3(a) 1810 x 1024 = 1853440 bytes 3(b) 60416 / 1024 = 59 GiB 3(c) 16 bits = 16 / 8 = 2 bytes 6144 x 2 bytes = 12288 bytes [ 3(d) Random access memory (RAM) • Main memory • Hard disk / Hard drive • Flash memory • Read-only memory (ROM) • Any other correct answer

4 Q4 4(a) 20 student names and 20 student temperatures 4(b) Names of students who have temperature 38 degrees or above and their respective temperatures. 4(c) • Store the 20 student names and temperature data in arrays / lists. • Search for students with temperature 38 degree or above.

5 Q5 5(a) Transfers required memory location from processor to memory. It is unidirectional. 5(b) Transfers data between memory and processor. It is bi-directional. Q6 Description Type of cyberattack A computer program that attaches itself to a normally harmless program and modifies it. Virus A computer program that pretends to be a harmless file or useful application but it can cause unauthorised access to the computer. Trojan horse A computer program that runs automatically and attempts to spread by sending copies of itself to other computers. Worm A small piece of data used by websites to store personal information on a user’s web browser. Cookie [4m]

6 Q7 7(a) The position of a digit in a binary number determines its place value, which is represented by 2N. The plac