To find the diver's depth after 5 minutes while descending at a rate of 8 m/min, we need to use expressions that correctly represent the rate and the time. The depth can be calculated as follows:
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Total Depth = Rate × Time: The diver descends 8 meters for each minute over 5 minutes, so the depth is calculated as:
- \(-8 \times 5\) (which gives -40 m, correctly representing the total depth).
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Adding Negative Depths: Using repeated addition or subtraction to represent the depths:
- \(-8 + (-8) + (-8) + (-8) + (-8)\) (which simplifies to -40 m),
- \(-8 - 8 - 8 - 8 - 8\) (which also simplifies to -40 m).
Now, let's evaluate the final option:
- \(-85\) does not represent the correct calculation for the depth after 5 minutes, as this does not relate to multiplying the rate (8 m/min) by the time (5 min).
Thus, the expression \(-85\) cannot be used to find her depth after 5 minutes.