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A researcher has calculated a 90% confidence interval for the mean weight in grams (µ) of a newborn baby and found it to be 2934 ± 222 grams. (Note that this means the the confidence interval is 2712 < µ < 3156). Determine whether the following statements is true or false.   If we took many additional random samples of the same size and from each computed a 90% confidence interval for µ, approximately 90% of these intervals would contain µ.

Is there a significant relationship between the number of stamens and the number of carpels?  Explain (using a hypothesis test).

View the three type of dose-response curves below – the top on is (a), the middle is (b) and the last one is (c). Which graph would most likely correspond to how a test on BPA (an endocrine disruptive chemical) would look like? 

Which of the following values of r indicates the most strongest relationship between two quantitative variables?

The   _______ the p-value, the stronger the evidence against the null hypothesis provided by the data.

The sum of the ranks for the three groups are: Cylinders Rank Sum 4 16 6 45 8 44   Find the value of the test statistic, H. What is the p-value of the test? What is the conclusion for the hypothesis test?

Fourteen mature flowers of a particular species were dissected, and the number of carpels and stamens present in each flower were counted.   Carpels (x) 27 31 28 22 26 29 30 30 24 25 22 29 28 25 Stamens (y) 52 68 70 45 61 50 56 65 43 37 36 74 38 35   Here is a graph of the data, along with the line of best fit (LSRL).   Use this data for the next three questions.

(same data as previous problem) The manager of a soda bottling plant is interested in comparing the performance of two bottling machines, the old machine and a new machine that has just been purchased. For each machine she selects 10 one-hour periods at random and records the number of crates completed in each hour. The table below gives the results. New 78 87 79 82 87 81 85 80 82 83 Old 74 77 78 70 87 83 76 78 81 76   (b)     Give a 90% confidence interval for the difference in the two means. (Don’t forget the sentence.)

Does the type of movie that children are watching make a difference in the amount of snacks they will eat?  Seventy-five randomly selected children were randomly assigned to watch either a cartoon, a science fiction, or a live action musical (25 to each). Cheese crackers were available in a bowl, and the investigators compared the number of crackers eaten by children while watching different kinds of movies. What are the response variable and the explantory variable in this study?

__________ argues that the propensity for crime commission evolved as part of the male reproductive strategy and a particular neurochemistry characteristic of males increases the probability of male criminality.