For the non-inverting amplifier shown in the figure, the input voltage is 1 V. The feedback network consists of 2 k$\Omega$ and 1 k$\Omega$ resistors as shown. If the switch is open, $V_o = x$. If the switch is closed, $V_o = ____ x$.
Consider the system described by the difference equation \[ y(n) = \frac{5}{6}y(n-1) - \frac{1}{6}(4-n) + x(n). \] Determine whether the system is linear and time-invariant (LTI).
Find the area of the square shown in the figure whose vertices are at $(0,0)$, $(1,1)$, $(2,0)$ and $(1,-1)$.