Final answer:
To calculate the total time it takes a diving bell to reach the maximum depth of 80 m, you would generally divide the depth by the velocity (T = d / V) if speed is constant and acceleration is not involved.
Step-by-step explanation:
The student's question regarding the experimental diving bell appears to ask for the calculation to determine the total time it takes the bell to reach the maximum depth of 80 m. The appropriate formula to calculate this would depend on the context and the variables provided. Usually, in problems such as this one related to kinematics or dynamics in physics, time is calculated by dividing the distance by velocity if acceleration is not considered (thus T = d / V fits the context if d is depth and V is velocity). However, to provide an exact answer, additional information about the conditions of the descent, such as the speed of the diving bell and whether it's constant, would be required. Without that information, we can only suggest that formula D is the most appropriate based on the information provided.