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Book page 149, Exercise A6, Question No 20.
To trim an aircraft for a higher nose attitude, the elevator trim tab must be deflected so as to provide a local lift force which acts -
(a) upwards to lift the elevator up
(b) upwards to push the elevator down
(c) downwards to lift the elevator up
(d) downwards to push the elevator down
The correct answer on next page says (a)
However the answer explanation in my opinion pertains to (c): When the elevator trim tab is deflected downwards it provides a force which acts upwards lifting the elevator to force the tail down - thus lifting the nose.
Can't find this in errata.