Explanation:
Volume of 10 coins = 100ml - 75ml = 25ml
Volume of 1 coin = 25ml / 10 = 2.5ml
The average volume of each coin is 2.5ml.
The answer is solar panels
I assume you are talking about the vertical distance: in that case, the answer is 0.6 m.
In fact, the wave's amplitude is the vertical distance between a crest of the wave and a trough. For the wave in the problem, this distance is equal to 0.6 m, therefore the amplitude of the wave is exactly 0.6 m.