Answer: Choice A
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Explanation:
The value of k determines the slope, or rate of change, of how fast the balloon is climbing per second.
For example, if k = 5, then that means the balloon is going upward at 5 feet per second (equivalent to roughly 3.41 mph)
If k = 5, then y = kt becomes y = 5t. Note how we have the following
- t = 0 leads to y = 0
- t = 1 leads to y = 5
- t = 2 leads to y = 10
- t = 3 leads to y = 15
and so on. Each time t goes up by 1, d goes up by 5. This is one way to see how the speed is 5/1 = 5 ft per second.
