The orange graph is going in increments of 100. Therefore, the numbers line up. Not only that, but since the blue graph has 200 per increment, it doesn't work. :)
Answer: Mrs.Buller collects a 500-ml sample of seawater for her chemistry class, and it has 1.94% of chlorine, we have to determine the amount of chlorine in the sample:
Therefore the chlorine content in 500ml of water is 9.7ml.
