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.
More recently the term combo drive is used to refer to an optical drive that can read & write CDs and DVDs, but only read Blu-ray Disc/BD-ROM; some manufacturers refer this as Blu-Ray Disc combo drive or BD-ROM/DVDÂ±RW/CD-RW drive.