A logic gate which gives output 'HIGH' only when its two input terminals are at different logic levels with respect to each other is

Choose the FALSE statement from the following.

In an n-p-n transistor 200 electrons enter the emitter in 10$$^{-8}$$ second. If 1% electrons are lost in the base, then the current that enters the emitter and the current amplification factor are respectively [e = 1.6 $$\times$$ 10$$^{-19}$$ C]

Combination of NAND gates is shown in the figure. It is equivalent to