Which operating system, usually distributed for free, relies on open source software that is developed by volunteers and contains code in the public domain?

A doughnut chart displays

A) relationships among three values by using bubbles. B) contains a single chart and no spreadsheet data. C) values as percentages of the whole but may contain more than one data series. D) enables you to adjust the size of the chart remotely.

Using the OSI model, what format does the Data Link layer use to format messages received from higher up the stack?

A. A datastream B. A frame C. A segment D. A datagram