1 From the secondhand account, the reader gets more background information about what the Oregon Trail was. 2  From the firsthand account, the reader gets a better understanding why it was so dangerous.
Printers generally age more by the number of pages printed rather than by pure years. The rule of thumb has always been whatever the recommended volume is (for instance 5000 pages per month for a P3005) multiplied by say five or six years so about 300,000 pages would be the life expectancy of the printer.
Pages vs. Time. Because printer manufacturers don't know how much you print, the primary cartridge life rating is in pages. For instance, a cartridge rated to yield 3,000 pages should last for approximately that number of pages. At the same time, many cartridges also have shelf lives.