For your experiment, you pour 5 glasses - one contains cola, one contains root beer, one contains ginger ale, one contains Mountain Dew, and one contains Dr. Pepper. In each glass, you place one untreated new nail, which you took pictures of before you started. You leave the 5 glasses undisturbed for a week. After the week is up, you take out the nails and compare them to the picture of the nails before you began the treatments.
Are the following dependent or independent variables?
Types of soda: independent or dependent?
Length of experiment: independent or dependent?
Amount of corrosion: independent or dependent?
5 glasses: independent or dependent?

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