In physics and engineering, in particular fluid dynamics and hydrometry, the volumetric flow rate, (also known as volume flow rate, rate of fluid flow or volume velocity) is the volume of fluid which passes per unit time; usually represented by the symbol Q (sometimes VÌ). The SI unit is m3/s (cubic metres per second).
The symptoms of the disease were black and purple spots on the body. The spots soon began to become enlarged and swollen. The victims were taken captive by death in about two to seven days. The plague lasted for four years, but it still remained a recurrent fear until the seventeenth century.
Beginning in 1347 and continuing for a full five years, a devastating plague swept Europe, leaving in its wake more than twenty million people dead. This epidemic now known as the Black Death was an outbreak of bubonic plague which had begun somewhere in the heart of Asia and spread westward along trade routes. The consequences to Europe were profound.