(a) i() What is firewall? (ii) List two methods used in protecting the computer system.

(b) Explain the following stages of the System Development Life Cycle: (i) feasibility study; (ii) design; (iii) maintenance.

(a) A musician intends to record music on a storage medium. List four ways that the music file can organized in the storage medium.

(b) State two basic operations on computer file. (c) Explain the following computer terms: (i) file (ii) re cord

(a) Explain the following terms: (i) storage device; (ii) virtual memory.

(b) Two storage devices have capacities 2KB and 2MB respectively. (i) Calculate the number of bits that each of 2KB and 2MB can hold. 2 KB: 2 MB

(i) Putting the two storage together, calculate the total capacity in bytes.

(a) (i) Identify Figure 1 above. (ii) Name the parts labeled I, J, K, and L in Figure 1

(b)(i) Define the documentation stage in the Program Development Life Cycle. (ii) List three characteristics of a good computer program.

(a)(i) Define the term encryption. (ii) Tick two authentication techniques involved in security measure from Table 1.

Table 1

  (ii) Outline two features of data encryption. (b) While exchanging data with a friend through your mobile phone, you observed that it took a longer time than usual. Outline four factors that may be responsible for the delay in the data transfer.