Откройте скобки и запишите глаголы в правильной форме. Bell's extensive knowledge of the nature of sound and his understanding of music (1) _ (to enable) him to conjecture the possiblity of transmitting multiple messages over the same wire at the same time. Although the idea of a multiple telegraph (2) _ (to be) in existence for some time, Bell (3) _ (to offer) his own musical or harmonic approach as possible practical solution. His "harmonic telegraph" (4) _ (to base) on the principle that several notes could be sent simultaneously along the same wire if the notes or signals different in pitch. He (5) _ (to prove) that different tones would vary the strength of an electric current in a wire.​

UlianaTir    3   04.05.2020 20:48    11