no mate its in the book page 77 mixed excersise 5E question 6)a)
If you don't like to take your time writing you full question then i think we shouldn't waste our time on you.
Yesterday you said that a question is in the C2 jan 2012 paper, without telling the board. Several times you have posted questions regarding the book, without telling which module you are talking about.
And right now the question you wrote wasn't complete.
Here is the question:
Don't mind, but i have tried to explain you several times to tell us the full question, if you talk about a book then tell the module, which book is it, and if exam paper remember to tell the board.