Need help with practice questions

7. The department of agriculture at a university was interested in determining whether a preservative was effective in reducing discoloration in frozen strawberries. A sample of 80 ripe strawberries was prepared for freezing. Then the sample was randomly divided into two groups of 40 strawberries each. Each strawberry was placed into a small plastic bag. The 40 bags in the control group were sealed. The preservative was added to the 40 bags elina containing strawberries in the treatment group, and then those bags were sealed. All bags were stored at 0 degree Celsius for a period of 6 months. At the end of this time, after the strawberries are thawed, a technician rated each strawberry's discoloration from 1 to 10, with a low score indicating little discoloration. The results from each sample are listed below Preservative group Control group n = 40 n = 40 x = 3.1 x = 4.05 S = 1.83 S = 2.141 a) Perform the appropriate procedure at a 0.05 significant level to find evidence that preservative was effective in lowering the average rating. Construct the appropriate confidence interval to estimate the difference in mean discoloration rating between the strawberries that were not treated with preservative and those made in (a)? Explain. that were treated with preservative. Does the interval you found coincide with the decision you