When a bipolar junction transistor is operating in the saturation mode, which one of the following statements is TRUE about the state of its collector-base (CB) and the base-emitter (BE) junctions?

In the following circuit, the transistor is in active mode and $${V_C} = 2V.$$ To get $${V_C} = 4V,$$ we replace $${R_C}$$ with $${R_C}.$$ Then the ratio $$R{'_C}/{R_C}$$ is __________.

The filters $${F_1}$$ and $${F_2}$$ having characteristics as shown in figures $$(a)$$ and $$(b)$$ are connected as shown in Figure $$(c).$$

The cut-off frequencies of $$F1$$ and $$F2$$ are $${f_1}$$ and $${f_2}$$ respectively. If $${f_1}\, < \,{f_2},$$ the resultant circuit exhibits the characteristic of a

The operational amplifier shown in the figure is ideal. The input voltage (in Volt) is $${V_i} = 2\sin \left( {2\pi \times 2000t} \right).$$ The amplitude of the output voltage $${V_0}$$ (in Volt) is __________.