Whether audible depends on many factors. Chesky has some tracks on one or two discs that attempt to demonstrate any audible effects of inverted polarity.
BUT, the first graph of nearly every amplifier review here seems to show the output in absolute time (that bottom axis is time). Any inverting amplifier should show an inversion of this output signal, unless an inversion is being performed on the input signal and we're not being told (seems unlikely).
Not if (as I assume) it works like an oscilloscope - in which case it is triggering on the rising edge and this will hide any inversion. Time on the x axis is from the trigger point.