A bus is an electrical path which data travels between the different components in an electronic device.
The correct answers are:
<span>E-commerce platformsMobile
Applications
Online point-of-sales systems
Source and explanation: https://goo.gl/guJKC9
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Telecommunications is the electronic transmission of signals for communications, which enables organizations to carry out their processes and tasks through effective computer networks

By definition a computer is an electronic device used to store and compute data. So, by definition a calculator stores and interprets data/numbers, and that makes it a computer. However, a computer can also use programs, and manipulate stored data to complete those programs.
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