What was the @ sign used for?
(Отметьте один правильный вариант ответа.)
Варианты ответа
Ray Tomlinson used the sign to identify the protocol.
Ray Tomlinson used the sign to write a letter.
Ray Tomlinson used the sign to designate the receiving machine.(Верный ответ)
Ray Tomlinson used the sign to identify the mail server.