?Case 3-1
All computers require software to operate and perform basic tasks. System software is the software that controls a computer and allows you to use it. Systems software consists of the operating system and utility programs. Many operating systems have been in use since mainframe computers. Identify the facts on each operating system in the following questions.
Joe is a professor at BuildTree University. During a lecture on computer software, he tells his students thatAT&T Bell Laboratories developed an operating systemin the late 1960s for midrange servers that could support a variety of devices from different manufacturers. Which of the following operating systems is Joe talking about?
A. ?UNIX
B. ?DOS
C. ?Linux
D. ?Mac OS
Answer: A
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would add /opt/bin to PATH only if that pathname is not already in PATH. Be sure your solution works even if the shell variable starts out empty. Also make sure you check the list elements carefully. If /usr/opt/bin is in PATH but /opt/bin is not, the example just given should still add /opt/bin to PATH. (Hint: You might find this exercise easier to complete if you first write a function locate_field that tells you whether a string is an element in the value of a variable.)
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What are electromagnetic interference (EMI) and radio frequency interference (RFI)?
What will be an ideal response?
Inside the parentheses of the for statement are three items, separated by ____.
a. dots b. commas c. colons d. semicolons