Answer:
Glucose for the first one, good luck on the second
Explanation:
The dependant variable would be the salmon, because they depend on the water and pollution levels to give a result.
The speed of a sound wave depends upon the medium through which it travels. In general, sound travels faster through solids than through liquids or gases. Also, the denser the medium, the slower sound will travel through it. The same sound will travel at a different speed on a cold day than it would on a warm day.
