I would give an unhesitating affirmative answer to both.
Times, Sunday Times (2008)
An affirmative answer often seems unavoidable.
The Times Literary Supplement (2014)
An affirmative answer could not be excluded.
Times, Sunday Times (2010)
An affirmative answer favours a physical cause.
Times, Sunday Times (2006)
An affirmative answer to this question is hardly possible.
Bramwell, Anna C Refugees in the Age of Total War (1988)