Consider the circuit shown in the figure. Assume base-to-emitter voltage V_BE=0.8 V and common base current gain $$\left(\alpha\right)$$ of the transistor is unity. The value of the collector-to–emitter voltage V_CE (in volt) is _______.

An npn bipolar junction transistor (BJT) is operating in the active region. If the reverse bias across the base-collector junction is increased, then

For a narrow base PNP BJT, the excess minority carrier concentration ($$\bigtriangleup n_E$$ for emitter, $$\bigtriangleup p_B$$ for base, $$\bigtriangleup n_E$$ for collector) normalized to equilibrium minority carrier concentration ($$\bigtriangleup n_{E0}$$ for emitter, $$\bigtriangleup p_{B0}$$ for base, $$\bigtriangleup n_{C0}$$ for collector) in the quasi-neutral emitter, base and collector regions are shown below. Which one of the following biasing modes is the transistor operating in?

The figure shows the I-V characteristics of a solar cell illuminated uniformly with solar light of power 100 mW/cm². The solar cell has an area of 3 cm² and a fill factor of 0.7. The maximum efficiency (in %) of the device is __________.