If magnetic tape (pre?1980s) was ½ inch wide and stored data in nine tracks at 128 characters/inch, what was the areal density in bits per square inch? What is the areal density ratio between this and the platters of modern disk drives?
What will be an ideal response?
If the tape is ½ inch wide, one square inch of tape would be two inches long. At a density of 128 characters per inch, the density is 256 characters per square inch. A character occupies 9 bits, which makes the areal density 9 × 256 = 2,304 bits/square inch.
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What is a summary sheet?
A) A worksheet with data on the left side and the summary on the right B) A sheet with two panes: one with the data, the other with the summary C) A worksheet where totals from other worksheets are displayed D) A worksheet with sheet names, sheet information, and sheet locations of all other worksheets
Create a new class called Dog that is derived from the Pet class given in Listing 6.1 of Chapter 6. The new class has the additional attributes of breed (type String) and boosterShot (type boolean), which is true if the pet has had its booster shot and false if not. Give your classes a reasonable complement of constructors and accessor methods. Write a driver program to test all your methods, then write a program that reads in five pets of type Dog and displays the name and breed of all dogs that are over two years old and have not had their booster shots.
This project would be easier to do with an array of type Dog, but how to write class constructors for arrays has not been covered, so the code to process one dog has to be repeated five times.