Below are instructions for using Excel to perform a T-test on data.

1. Open a new Excel spreadsheet.
2. In cell A1, type the variable name (e.g. Normal).
3. In subsequent cells below A1, type the numerical metabolic rate data.
4. In cell B1, type the other variable name (e.g. Ephedrine-treated).
5. Click on any blank cell (e.g. immediately below the last number in Column A).
6. From the "Insert" menu, select "Function"
7. From the dialog box that appears, select "Statistical" from the "Function Category" column and "TTEST" from the "Function Name" column. Scroll down as necessary.
8. In the dialog box that appears, type "A1:Ax" in the line labeled "Array 1", where x is the number of the last cell in column A with data (e.g. A1:A5).
9. Type B1:Bx for Array 2 (e.g. B1:B5)
10. Type "1" for "Tails".
11. Type "2" for "Type".
12. Click the "OK" button

Excel will return a probability value for you. If the number is < .05, then there is a statistically significant failure of the data to support the null hypothesis (Normal > ephedrine-treated), so you may accept the alternate hypothesis (Normal < ephedrine-treated). Otherwise, accept the null hypothesis.

If you prefer to have Excel calculate metabolic rate for you, the set up below works well. In Cell J3 (note two narrow columns put in for separators), I put the following formula:

=15/B3*273/(273+C3)*734/760*3600*4.8*10/(0.437+(2.143*D3))

B3 is the datum for seconds

C3 is temperature

D3 is weight

I then clicked on cell J3 and drug down to J10 and selected "Fill" and "Down" from the "Edit" menu. I built a similar formula in K3:K10 referring to the proper cells in the formula. I used the average function in Cells J11 and K11, the standard Deviation function in J and K 12 and the T-test function in K 14 as described above.

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