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Which one of the following is not an assumption when we perform an Analysis of Variance?

A randomized block design yielded the following Analysis of Variance table:       Source             df        SS                MS                F Total                 14      836       Treatments        4       501       125.25 Blocks                2       225       112.50 Error                  8       110          13.75                      Find the critical F value from the F tables that should be used to compare to the calculated F value for treatments.  Assume that we will use a significance level (α) of 0.05.

Assume that the probability that a calf will be red in color is 0.25 and the probability that the calf will have horns is 0.50.  Coat color and the presence or absence of horns are independent events.  What is the probability that the calf will be red and will have horns?

The weights in pounds of 23 dogs were used to construct the following stem-and-leaf display using the first digit as the stem and the second digit as the leaf:. Stem     Leaves                                                    3            2     4 4            0     3     4     5     7     8     9 5            0     1     2     3     4     5 6            1     2     5     6     7 7            0     1 8 9            8 Use the stem-and-leaf display to find the upper quartile.

An animal scientist is interested in determining the proportion of ewes (i.e., female sheep) that give birth to twins.  Rather than examine the records for all ewes in the United States, the animal scientist randomly selects 500 ewes and finds that 220 of them gave birth to twins. Construct a 99% confidence interval to estimate the true population proportion of ewes, p, who give birth to twins.  Interpret the meaning of this confidence interval.

The mean grade on an Organic Chemistry exam is a 50 and the standard deviation of the grades is 10.  The highest grade in the class was a 95.  Calculate the z-score for the student with the highest score of 95.  Based in the z-score, is this grade of 95 an outlier?  Why or why not?

Suppose that 80% of the Holstein cows in the U.S. give birth to their calves with no calving difficulty.  We randomly select 7 Holstein cows from the population consisting of all Holstein cows in the U.S.  What is the probability that at least 5 of the 7 (i.e., 5 or more) cows in this sample will give birth to their calves with no calving difficulty?  To find the answer to this question, you can use the equation for the binomial distribution or a binomial probability table.

Find the sample size needed to estimate the population proportion (p) correct to within 0.06 with probability 0.95.  Assume that we have previous information that indicates that p = 0.30.

The average weight of a kennel of dogs is 40 lb and the standard deviation of the weights is 5 lb.  Find the probability that a randomly selected dog will weigh more than 48 lb.

A Gallop poll is conducted to estimate the proportion of voters who plan to vote in favor of a certain issuse on the ballet.  A random sample of 500 people of voting age is selected.  Results of the poll show that 300 of the 500 people polled plan to vote in favor of the issue.  Perform the calculations needed to determine whether or not it would be appropriate to construct a large-sample confidence interval for the true population proportion.  What do you conclude (i.e., is it appropriate?