<quizlib id=„quiz1“ rightanswers=„'a3'“ submit=„check answers“>

  <question title="How is the output resistance of an amplifier defined?" type="checkbox">

$R_O = \Delta U_I / \Delta I_O$| $R_O = U_I / I_O$| $R_O = \Delta U_O / \Delta I_O$| $R_O = -\Delta U_O / \Delta I_O$| $R_O = U_O / I_O$ </question></quizlib>