Answer:
The equation that models the relationship between the time x (in minutes) and the distance y (in feet) from the ground is:
y = 2000x
This is because for every 2 minutes that go by (i.e. for every increase of x by 1), the balloon rises by 2000ft (i.e. a constant rate of change). So, the equation y = 2000x represents a straight line with a slope (rate of change) of 2000, passing through the origin.