4. In the common-emitter amplifier shown below (from page 14 of last week’s notes), imagine that we apply a small upward wiggle, ∆V , at the base. Explain the sequence of steps that leads us to conclude that we see a resulting downward wiggle, −5∆V , at the collector. (“VB increases by ∆V . Thus VE changes by . . . . Thus IE changes by . . . . Thus IC . . . . Thus VC . . . .”)