After collecting data, each student needs to work with one partner to construct a data table and graph for either the nitrate or phosphate data from the 3 creeks. One student turns in the nitrate data and graph, the other student turns in the phosphate data and graph.

Data Tables:

An example of what to do when creating tables and graphs.

a) Add a descriptive title for both the raw data table and final data table (See example.).

b) Units are listed.

c) Mean data and standard deviation have been calculated using Microsoft EXCEL. (Directions here.)

Graphs:

a) Mean data is shown for each creek along with standard deviation error bars. (Directions here.)

b) Title (Should be the same as for your final data table.) should be displayed atop your graph.

c) X and Y axes should be labelled, with units listed on the Y axis.

Conclusion: (A paragraph of results.)

a) List the mean nitrate or phosphate levels (which ever data you graphed) plus standard deviation for each of the 3 creeks. (Example: 37.3 mg/L NO3 +/- 2.4 mg/L).

b) Rank the 3 creeks from least to most (or most to least) in terms of the pollutant you graphed. Higher bars = more pollutant. Some of the bars will be nearly the same. Check the error bars. If they are very close or if they overlap, the data for those creeks is inconclusive. More tests would need to be run to conclude whether those tests could clearly be ranked! If the error bars are fairly wide, this indicates that the people who tested the water for that pollutant did not do a very consistent job of it.