Which method was used by only pass a single bit ( )?
A. Semaphore
B. Satellite
C. Electrical telegraph
D. Chains of beacons
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Please select the correct statement on below ( ).
A. Talking drums were used by natives in Africa, New Guinea and South America, and smoke signals in North America and China.
B. Talking drums were used by natives in China, New Guinea and South America, and smoke signals in North America and Africa.
C. Smoke signals were used by natives in China, New Guinea and South America, and talking drums in North America and Africa.
D. Smoke signals were used by natives in Africa, New Guinea and South America, and talking drums in North America and China.
The five-needle, six-wire system which patented by Charles and William was used commercially in the year of ( ).
A. 1816
B. 1838
C. 1839
D. 1844
The first commercial telephone service were setup in ( ) on both sides of the ( ).
A. 1876 and 1878, Atlantic in the cities of New Haven and London.
B. 1876 and 1878, Pacific in the cities of Los Angeles and Shanghai.
C. 1878 and 1879, Atlantic in the cities of New Haven and London.
D. 1878 and 1879, Pacific in the cities of Los Angeles and Shanghai.
Human voice was able to transmit wirelessly due to the contribution of ( ).
A. Guglielmo Marconi
B. Karl Braun
C. Reginald Fessenden
D. Philo Farnsworth
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