Using offset-nulling facilities provided for the op amp, a closed-loop amplifier with gain of+1000 is adjusted at 25°c to produce zero output with the input grounded. if the input offset-voltage drift is specified to be 20 μv/°c, what output would you expect at 0°c and at 100°c? while nothing can be said separately about the polarity of the output offset at either 0 or 75°c, what would you expect their relative polarities to be?