Around 1960, computer software is greatly improved and the first programming languages app
此题为判断题(对,错)。
此题为判断题(对,错)。
The main idea of Paragraph 5 is ______.
A.to tell people there are various products against computer viruses
B.that there are 1100 known viruses now plaguing personal computers
C.some of virus protection products have their strengths and weaknesses as well
D.that the existing virus protection products can destroy all kinds of viruses
Which of the following is not true?
A.In 1959, IBM made its first commercial transistorized computer.
B.In 1961, the first commercial integrated circuit came into being.
C.In 1962, the second generation of computers started.
D.In 1963, the first advance was the production of the Model 33 keyboard.
A.1981
B.1960
C.1980
D.1992
According to the passage, cell phones were launched______.
A.in the late 1970s
B.between 1955 and 1960
C.in the late 1955s
D.in the early 1990s