Calculator is (66) for performing arithmetic operations, but that requires human intervention to alter its stored program, if any, and to initiate each operation or sequence of operations. A calculator performs some of the functions of a computer, but usually operates only with frequent human intervention.

Microcomputer’s processing unit consists of one or more microprocessors, and includes storage and input-output (67) . Personal computer primarily intended for (68) use by an individual. (69) computer can be hand-carried for use in more than one location. Minicomputer is functionally intermediate between a microcomputer and a mainframe. And supercomputer has the highest processing speeds available at a given time for (70) scientific and engineering problems.

（66）处填（）。

A．suitable

B．well-formed

C．applicable

D．usable

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