The following data were taken from a research article in the Canadian Journal of Fisheries and Aquatic Sciences, Vol. 57, page 126-127 (2000). The study examined the concentration of various heavy metals in the soft tissues of 2 species of snails in two different lakes along the St. Lawrence River. Cadmium (Cd) levels (microgram/gram dry weight) in soft tissues of Physa gyrina collected in Lake St. Pierre (LSP) and in Lake St. Louis (LSL) in 1990 and 1991 respectively. LSL LSP 7.46 1.02 0.64 1.15 0.40 3.74 0.77 0.71 2.24 0.77 0.96 0.37 0.75 0.45 1.33 1.91 1.00 0.85 Use the t test to determine if there is a significant difference in the Cadmium concentration in snail soft tissue between the two lakes. 1. State your null hypothesis (Ho) 2. Calculaten (sample size for each lake) 3. Calculate x (mean) for each lake 4. Calculate the Variance (s²) for each lake 5. Plug your values into the t test equation and find “calculated t" 6. Determine the df (degrees of freedom) 7. Look up “critical t" with a p value of 0.05 8. Accept of Reject the null hypothesis 9. Conclude if there is a statistical difference or not between the soft tissue levels of Cd in snails from these two lakes.

The following data were taken from a research article in the Canadian Journal of Fisheries and Aquatic Sciences, Vol. 57, page 126-127 (2000). The study examined the concentration of various heavy metals in the soft tissues of 2 species of snails in two different lakes along the St. Lawrence River. Cadmium (Cd) levels (microgram/gram dry weight) in soft tissues of Physa gyrina collected in Lake St. Pierre (LSP) and in Lake St. Louis (LSL) in 1990 and 1991 respectively. LSL LSP 7.46 1.02 0.64 1.15 0.40 3.74 0.77 0.71 2.24 0.77 0.96 0.37 0.75 0.45 1.33 1.91 1.00 0.85 Use the t test to determine if there is a significant difference in the Cadmium concentration in snail soft tissue between the two lakes. 1. State your null hypothesis (Ho) 2. Calculaten (sample size for each lake) 3. Calculate x (mean) for each lake 4. Calculate the Variance (s²) for each lake 5. Plug your values into the t test equation and find “calculated t" 6. Determine the df (degrees of freedom) 7. Look up “critical t" with a p value of 0.05 8. Accept of Reject the null hypothesis 9. Conclude if there is a statistical difference or not between the soft tissue levels of Cd in snails from these two lakes.

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Description: The following data were taken from a research article in the Canadian Journal ofFisheries and Aquatic Sciences, Vol. 57, page 126-127 (2000). The study examined theconcentration of various heavy metals in the soft tissues of 2 species of snails in t

MATLAB: An Introduction with Applications

6th Edition

ISBN:9781119256830

Author:Amos Gilat

Publisher:Amos Gilat

Chapter1: Starting With Matlab

Section: Chapter Questions

Problem 1P

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