D1 January 2005 Q2
2. The precedence table for activities involved in producing a computer game is shown below.
| Activity | Must be preceded by |
|---|---|
| \(A\) | – |
| \(B\) | – |
| \(C\) | \(B\) |
| \(D\) | \(A, C\) |
| \(E\) | \(A\) |
| \(F\) | \(E\) |
| \(G\) | \(E\) |
| \(H\) | \(G\) |
| \(I\) | \(D, F\) |
| \(J\) | \(G, I\) |
| \(K\) | \(G, I\) |
| \(L\) | \(H, K\) |
An activity on arc network is to be drawn to model this production process.
(a) Explain why it is necessary to use at least two dummies when drawing the activity network. (2)
(b) Draw the activity network using exactly two dummies. (5)
| Scheme | Marks |
|---|---|
| \(D\) depends on \(A\) and \(C\), but \(E\) depends on \(A\) only | B1 |
| \(H\) depends on \(G\) only, but \(J\) and \(K\) depend on \(G\) and \(I\) | B1 |
| (2) |
| Scheme | Marks |
|---|---|
e.g. | M1 A1 A1 A1 A1 |
| (5) | |
| (7 marks) |