Later, during the Koine Greek period, the aspirated and voiceless stops /tʰ d/ of Attic Greek lenited to voiceless and voiced fricatives, yielding /θ ð/ in Medieval and Modern Greek.
If it is possible to answer this question, answer it for me (else, reply "unanswerable"): Attic Greek lenited to what?
Ah, so.. voiceless and voiced fricatives

In a switching circuit, the idea is to simulate, as near as possible, the ideal switch having the properties of open circuit when off, short circuit when on, and an instantaneous transition between the two states. Parameters are chosen such that the "off" output is limited to leakage currents too small to affect connected circuitry; the resistance of the transistor in the "on" state is too small to affect circuitry; and the transition between the two states is fast enough not to have a detrimental effect.
If it is possible to answer this question, answer it for me (else, reply "unanswerable"): What might stop a switch from transitioning quickly? 
Ah, so.. unanswerable

At the time of the Roman Empire, about two thousand years ago, various tribes, which spoke Celtic dialects of the Insular Celtic group, were inhabiting the islands. The Romans expanded their civilisation to control southern Great Britain but were impeded in advancing any further, building Hadrian's Wall to mark the northern frontier of their empire in 122 AD. At that time, Ireland was populated by a people known as Hiberni, the northern third or so of Great Britain by a people known as Picts and the southern two thirds by Britons.
If it is possible to answer this question, answer it for me (else, reply "unanswerable"): The people that lived in the British Isles during the Roman Empire era spoke which language?
Ah, so..
Celtic dialects of the Insular Celtic group