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Support of Growth Difference


Nanobubbles are tiny gas bubbles that are less than 200 nanometers in size. These bubbles have properties that can have important impacts on living organisms. Researchers have conducted studies on the impact of nanobubble water on both plants and animals.

In one study, plants were grown hydroponically with either normal water or air-based nanobubble water for 4 weeks. The changes in height, length, and weight of the plants were measured, as shown in Graph 1. In a second study, fish were grown in both normal water and air-based nanobubble water, and the change in their weight was recorded after either 3 or 6 weeks as shown in Table 1.

Graph 1

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Table 1

Fish Type Kept for Normal Water Nanobubble Water
Sweetfish 3 weeks Initial weight (kg) 3.0 3.0
Final weight (kg) 6.4 10.2
Rainbow Trout 6 weeks Initial weight (kg) 50.0 50.0
final weight (kg) 129.5 148.0

Which of the following would be the best evidence to support this statement: "Of all the tested samples, the sweetfish had the largest difference in growth between the samples grown in normal water as compared to nanobubble water"?


The sweetfish grew by 110% in normal water, while the rainbow trout grew by 160% in normal water.


Plants grown in nanobubble water had nearly 30% more mass.


The rainbow trout grew by 36 percentage points more in nanobubble water than in normal water.


The sweetfish grew by 130 percentage points more in nanobubble water than in normal water.