Answer:
108.7 ft
Explanation:
Put 30 where x is and do the arithmetic.
y = -3.29·30 -10 = -98.7 -10 = -108.7
The trend line predicts the depth to be 108.7 ft after 30 minutes.
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Comment on this problem
Real-world considerations in scuba diving may cause the diver to level off or head toward the surface before 30 minutes elapse. The trend line does not model these effects.