Trading losses (Sole trader)

Hello Tax tutor,
I must tell you this first that I am truly enjoying your lectures.
They are superb! I’ve become a huge fan of yours.

I am practicing some revision questions before moving on to Ch. 9 Employment income and I’ve got several questions. They are all from Kaplan exam kit.

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Q41.
Brooke has been trading profitably as a sole trader for many years. However, in the year ended 31 August 2014 she made a trading loss of £65,000.
Brooke has the following income in the tax year 2015/16:

Trading profit for year ended 31 August 2015 £12,000
Dividend income (gross) £9,000
Property income (furnished holiday accommodation) £4,000
NS&I savings certificate interest £1,000

What is Brooke’s net income for the tax year 2015/16 assuming she carries the trading loss forward?

£ [ ]
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The answer is £13,000 but I arrived at £12,600 only because I deducted 10% wear and tear from property income to derive assessable property income.
I wasn’t sure whether or not I was expected to adjust the property income in the question. Did I fall into the trap?

Another question is too simple to post in a separate thread.
Is ‘Gilt edged security’ a NS&I Certificate (Exempt) or NS&I investment (Taxable)?

Many thanks in advance.