Final answer:
The diver's average change in elevation per minute is approximately 3.6 feet per minute, which is calculated by dividing the total descent of 34.92 feet by the time spent, which is 9.7 minutes.
Step-by-step explanation:
To calculate the diver's average change in elevation per minute, we need to divide the total change in elevation by the total time taken. The total change in elevation is 34.92 feet, and the time taken is 9.7 minutes. So, the average change in elevation per minute would be:
Average change in elevation per minute = Total change in elevation / Total time taken
Average change in elevation per minute = 34.92 feet / 9.7 minutes = 3.6 feet per minute (approximately).
This result represents the rate at which the diver descended, which means on average, the diver went down by 3.6 feet for every minute spent underwater.