Answer:
not enough information
Step-by-step explanation:
Dividing altitude by hours, we find the ratios to be 400/2 = 200 ft/h and 700/6 = 116 2/3 ft/h.
These are not the same ratio, so altitude is not proportional to time.
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However, that's not what the question asks. It ask about rate of change. We only have enough information to determine the rate of change between hour 2 and hour 6 is 300 ft in 4 hours, or 75 ft/hour. Since we don't have any other rate of change information, we cannot determine if the rate of change is proportional to anything.
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<em>Comment on the question</em>
We suspect the question is simply worded poorly, and that we're supposed to determine if altitude is proportional to hours. (It is not). If that is actually the question, "rate of change" needs to be left out of the question.
