What unit of measurement is used to describe the rate of change?

Derivative

Who was the wife of Isaac? In "Apex Legends," what is the name of the playable Legend who can create dimensional portals? What famous jazz musician played the clarinet and band-led the world's first jazz concert at Carnegie Hall? Who was the Carthaginian princess and legendary founder of the city of Carthage? Which character was famously overweight as a teenager?