(a) Identify Singapore Telecommunication Ltd's sources of revenue.
(b) Describe the revenue recognition criteria applied by Singapore Telecommunication Ltd in relation to:
(i) Phone cards and prepaid cards
(ii) Fibre rollout
(iii) Provision of equipment
(c) Justify why income recognition on a 'percentage of completion basis' for the provision of information technology and engineering services and fibre rollout is an appropriate revenue recognition policy.