Life expectancy at birth, at 65, and 75 years of age by sex, race and Hispanic origin Health, United States 2015, table 15 [PDF - 9.8 MB] Life expectancy at birth and at 65 years of age, by sex: Organisation for Economic Co-operation and Development (OECD) countries Health, United States 2015, table 14 [PDF - 9.8 MB]
Multitasking, in an operating system, is allowing a user to perform more than one computer task (such as the operation of an application program) at a time. The operating system is able to keep track of where you are in these tasks and go from one to the other without losing information.
Preemptive multitasking is task in which a computer operating system uses some criteria to decide how long to allocate to any one task before giving another task a turn to use the operating system. The act of taking control of the operating system from one task and giving it to another task is called preempting.