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A state energy agency mailed questionnaires on energy conservation to 1,000 homeowners in Columbus.  Suppose an experiment consists of randomly selecting one of the returned questionnaires.  Consider the events:    Event A:  the home is constructed of brick    Event B:  the home is more than 30 years old    Event C:  the home is heated with oil A home that is constructed of brick and is less than or equal to 30 years old would be represented by which one of the following?

A population of rabbits has a mean weight of 12 lb with a standard deviation of 3 lb.  A rabbit breeder selects 1,000 samples of 36 rabbits each from this population, calculates the mean weight of the rabbits in each of these 1,000 samples, and then graphs the 1,000 sample means.  The mean of these 1,000 sample means is expected to be equal to:

A perfect negative correlation between variables X and Y indicates that the correlation between these two variables is equal to __________.

Find the area under the normal curve between z = -1.25 and z = 1.75.

If an interaction exists in a factorial experiment, tests of the main effects are not relevant, because differences in the mean levels of factor A are not the same across all levels of factor B.

The mean length of time required to complete a 5K race was 20 minutes.  The standard deviation of the times was 4 minutes.  The racing times were approximately normally distributed.  What is the probability that a randomly selected runner completed the race in less than 16 minutes?

A Randomized Block Design is used to compare fleece weights of three breeds of sheep – Merino, Suffolk, and Dorset (we can think of the three breeds as being the three treatments).  The sheep are divided into two weight classes (i.e., two blocks).  Block one contains sheep weighing less than 150 lb and block two contains sheep weighing more than 150 lb.  The fleece weights (in pounds) are as follows:                    Merino          Suffolk          Dorset Block 1          13                  8                  9 Block 2          14                  9                 11                                                                          The partially completed ANOVA table for this experiment is as follows: Source     df          SS            MS            F      Total                29.33333 Breed              26.33333     13.16667    79.00003 Block                     Error                 0.33333        0.16667              The correct degrees of freedom for total, breed, block, and error, respectively are:

A randomized block design is used to compare litter sizes of the Yorkshire and Duroc breeds of sows.  Blocking is used in an attempt to remove the effects of sow age, since it is known that sow age influences litter size.  Each block contains sows of similar ages.  The data collected for this experiment are as follows:                   Yorkshire       Duroc       Block totals Block 1          9 pigs         7 pigs         16 pigs Block 2         10                8                18 Block 3         11                9                 20 Block 4         13              10                 23                                                                             Totals           43              34                 77   The partially completed ANOVA table for this experiment is as follows:   Source          df          SS          MS          F        Total                        23.875 Breed                      10.125      10.125      81.0 Block                       13.375       Error                          0.375                                   Calculate the mean square for blocks and the mean square for error.

Find the standard deviation of a binomial probability distribution with a sample size of n = 40 and a probability of success of 0.40.

Heights of 50 trees in a nursery are an example of a ____________ variable.