Question

multiple choice the scientists from the previous scenario next look at how silicon dioxide concentration might be related to coral health. based on this data, which statements below best describe the association between the level of silicone dioxide present and the health of the coral reef and the way the relative frequency table is analyzing the data? select all that apply. a there appears to be an association between coral health and the level of silicon dioxide concentration. b the table is analyzing the data by the coral’s silicone dioxide levels. c the table is analyzing the data by the health of the coral. d there does not appear to be an association between coral health and the level of silicon dioxide concentration. | healthy | unhealthy | total | low silicone dioxide | 44% | 56% | 100% | high silicone dioxide | 46% | 54% | 100% |

Explanation:

• For option A: To check for an association, we compare the conditional distributions. For healthy coral, the percentage with low silicon dioxide is 44% and with high is 46% (small difference). For unhealthy coral, low is 56% and high is 54% (also small difference). So no strong association, so A is incorrect.
• For option B: The table has rows for low and high silicon dioxide and columns for healthy/unhealthy coral, so it's analyzing coral health by silicon dioxide levels (the independent variable here), so B is correct.
• For option C: The table is looking at how silicon dioxide levels relate to coral health (healthy or unhealthy), so it is analyzing the data by the health of the coral (the dependent variable), so C is correct.
• For option D: As calculated in A, the percentages for healthy and unhealthy across low/high silicon dioxide are very close (44% vs 46% for healthy; 56% vs 54% for unhealthy), so there's no apparent association, so D is correct.

Answer:

B. The table is analyzing the data by the coral’s silicone dioxide levels, C. The table is analyzing the data by the health of the coral, D. There does not appear to be an association between coral health and the level of silicon dioxide concentration.