For this unit Refers to Student’s Book pages Writing headlines

Students discuss the questions in pairs and then feed back to the class.
    b 
Students read the brief and answer the questions.
 Answers
1  In many ways, a radio commissioning brief is like a job advertisement: it 
describes a product/service that a person/company wants to be provided with; 
in this case, London 1 is looking for producers to make documentaries.
2  Somebody in London 1’s commissioning team.
3  People, most likely producers, who want to and are able to produce short radio 
documentaries.
4  This document was taken from the London 1 website; another place to find 
briefs such as this would be in trade papers.
    c