$6.$ Draw up an activity network for the following scenario:

The specification of an IT application is estimated as likely to take two weeks to complete.

When this activity has been completed, work can start on three software modules, A$,$B and C$.$

Design$/$coding of the modules will need $5,10$ and $10$ days respectively. Modules A and B can

only be unit $-$tested together as their functionality is closely associated. This joint testing should

take about two weeks. Module C will need eight days of unit testing. When all unit testing has

been completed, integrated system testing will be needed taking a further three weeks. This

testing will be based on the functionality described in the specification and will need $10$ days

of planning