Question A cell phone plan charges $15 per month for unlimited call and text messages, however each gigabyte (GB) of data is charged at a rate of $5 per GB. Assume that fractional values of a GB are prorated according to this rate. If a user uses more than 7 GB of data during their monthly billing cycle, then they are not charged more than the cost for the first 7 GB. Write a piecewise-defined function that describes the amount a cell phone user will pay, C, as a function of the number of GB of data they use, d, over the course of a month. (You may enter the intervals using either interval notation or as an inequality. Do not include the dollar sign in any of your answers.) Provide your answer below: The first piece of C(d) is [ ], defined in the interval [ ]. The second piece is [ ] defined in the interval [ ].
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If a user uses 0 to 7 GB of data, they will pay $15 for unlimited call and text messages, and $5 per GB of data. So the cost will be $15 + 5d. Show more…
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