1. Fluctuations of aggregate economic activity. 2.Cycles Expansion/Boom and Contraction/Recession. Peak and Trough: They are the turning Points of the business cycle. 3. Comovements of many macro variables over the business cycle.
Section 5: Using external media: CDs, DVDs and removable USB storage devices. â¢ dvd-r:until about 2005 the most common and portable format; cannot be erased or reused. â¢ dvd-rw:are-writable version of-rformat, similar to cdrw format CD discs.
Such discs are known as DVD-ROM, because data can only be read and not written or erased. Blank recordable DVD discs (DVD-R and DVD+R) can be recorded once using a DVD recorder and then function as a DVD-ROM. Rewritable DVDs (DVD-RW, DVD+RW, and DVD-RAM) can be recorded and erased many times.