possible Submit quiz A researcher studies water clarity at the same location in a lake on...

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possible Submit quiz A researcher studies water clarity at the same location in a lake on the same dates during the course of a year and repeats the measurements on the same dates 5 years later. The researcher immerses a weighted disk painted black and white and measures the depth (in inches) at which it is no longer visible. The collected data is given in the table below. Complete parts (a) through (c) below. Observation 1 2 3 4 5 6 Date Initial Depth, X; Depth Five Years Later, Y; 1/25 3/19 55.5 67.6 60.5 63.8 67.2 64.6 5/30 7/3 9/13 11/7 74.8 40.9 44.9 78.1 46.5 46.5 ... a) Why is it important to take the measurements on the same date? A. Using the same dates makes the second sample dependent on the first and reduces variability in water clarity attributable to date. B. Those are the same dates that all biologists use to take water clarity samples. C. Using the same dates makes it easier to remember to take samples. D. Using the same dates maximizes the difference in water clarity. b) Does the evidence suggest that the clarity of the lake is improving at the = 0.05 level of significance? Note that the normal probability plot and boxplot of the data indicate that the differences are approximately normally distributed with no outliers. his questio possible 1 point(s) Submit quiz A researcher studies water clarity at the same location in a lake on the same dates during the course of a year and repeats the measurements on the same dates 5 years later. The researcher immerses a weighted disk painted black and white and measures the depth (in inches) at which it is no longer visible. The collected data is given in the table below. Complete parts (a) through (c) below. Observation 1 2 Date 1/25 Initial Depth, Xi Depth Five Years Later, Y; 3 3/19 5/30 55.5 67.6 60.5 63.8 67.2 64.6 4 5 6 7/3 9/13 11/7 74.8 40.9 44.9 78.1 46.5 46.5 A. -9 0 2 B. -9 0 2 + 4 ... i C. -9 0 2 (U,N) More D. -9 0 2 Next A researcher studies water clarity at the same location in a lake on the same dates during the course of a year and repeats the measurements on the same dates 5 years later. The researcher immerses a weighted disk painted black and white and measures the depth (in inches) at which it is no longer visible. The collected data is given in the table below. Complete parts (a) through (c) below. Observation 1 2 3 4 5 6 Date 1/25 3/19 5/30 7/3 9/13 11/7 Initial Depth, X Depth Five Years Later, Y; 63.8 55.5 67.6 60.5 74.8 67.2 64.6 78.1 40.9 44.9 46.5 46.5 6- Difference U Z 6- -y U 2 -y U z U Z Difference Difference Difference Does this visual evidence support the results obtained in part b)? A. No because the boxplot supports that the lake is not becoming more clear, since most differences are positive or near 0. B. No because the boxplot supports that the lake is not becoming more clear, since most differences are negative. C. Yes because the boxplot supports that the lake is becoming more clear, since most differences are negative. D. Yes because the boxplot supports that the lake is becoming more clear, since most differences are positive or near 0. possible Submit quiz A researcher studies water clarity at the same location in a lake on the same dates during the course of a year and repeats the measurements on the same dates 5 years later. The researcher immerses a weighted disk painted black and white and measures the depth (in inches) at which it is no longer visible. The collected data is given in the table below. Complete parts (a) through (c) below. Observation 1 2 3 4 5 6 Date Initial Depth, X; Depth Five Years Later, Y; 1/25 3/19 55.5 67.6 60.5 63.8 67.2 64.6 5/30 7/3 9/13 11/7 74.8 40.9 44.9 78.1 46.5 46.5 ... a) Why is it important to take the measurements on the same date? A. Using the same dates makes the second sample dependent on the first and reduces variability in water clarity attributable to date. B. Those are the same dates that all biologists use to take water clarity samples. C. Using the same dates makes it easier to remember to take samples. D. Using the same dates maximizes the difference in water clarity. b) Does the evidence suggest that the clarity of the lake is improving at the = 0.05 level of significance? Note that the normal probability plot and boxplot of the data indicate that the differences are approximately normally distributed with no outliers. his questio possible 1 point(s) Submit quiz A researcher studies water clarity at the same location in a lake on the same dates during the course of a year and repeats the measurements on the same dates 5 years later. The researcher immerses a weighted disk painted black and white and measures the depth (in inches) at which it is no longer visible. The collected data is given in the table below. Complete parts (a) through (c) below. Observation 1 2 Date 1/25 Initial Depth, Xi Depth Five Years Later, Y; 3 3/19 5/30 55.5 67.6 60.5 63.8 67.2 64.6 4 5 6 7/3 9/13 11/7 74.8 40.9 44.9 78.1 46.5 46.5 A. -9 0 2 B. -9 0 2 + 4 ... i C. -9 0 2 (U,N) More D. -9 0 2 Next A researcher studies water clarity at the same location in a lake on the same dates during the course of a year and repeats the measurements on the same dates 5 years later. The researcher immerses a weighted disk painted black and white and measures the depth (in inches) at which it is no longer visible. The collected data is given in the table below. Complete parts (a) through (c) below. Observation 1 2 3 4 5 6 Date 1/25 3/19 5/30 7/3 9/13 11/7 Initial Depth, X Depth Five Years Later, Y; 63.8 55.5 67.6 60.5 74.8 67.2 64.6 78.1 40.9 44.9 46.5 46.5 6- Difference U Z 6- -y U 2 -y U z U Z Difference Difference Difference Does this visual evidence support the results obtained in part b)? A. No because the boxplot supports that the lake is not becoming more clear, since most differences are positive or near 0. B. No because the boxplot supports that the lake is not becoming more clear, since most differences are negative. C. Yes because the boxplot supports that the lake is becoming more clear, since most differences are negative. D. Yes because the boxplot supports that the lake is becoming more clear, since most differences are positive or near 0.