Parabola
It's not always easy to visualize this stuff. Do a Google image search for "3D Conic Sections" and take a look at a bunch of the results. That may help a bit. Let me know if you have any other questions.
840 = 70% (100% - 30%)
840 : 70 * 100 =
1200$ is your answer
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1200 - 30% = 840%
The rate of change is -50 based on the information given.
You would have to substitute the amount of months into the equation for x to properly determine the average rate of change, which is not posted in this question.
The number of kilograms and divided it by 94 tons