The diagram below shows a filament bulb labelled 60 W.

1. aName the physical quantity which the 60 W value labelled on the bulb represents. [1]
2. bPeople are encouraged to replace filament bulbs with fluorescent bulbs rated between 10 W and 30 W. State why it is advisable. [1]
3. cShow the energy changes that take place in a lit filament bulb. [2]

You'll mark your own answer against the marking guide when you hand it in.