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What is the weight of each category of grading for this cour…

What is the weight of each category of grading for this course? Fill in correct value in each space (please note the percent sign is already written): 3 Unit Tests + Final Exam:    [Test]%Weekly Quizzes:                    [Quiz]%Homework:                            [HW]%Project:                                   [Proj]%

A medical research team conducted a study to test the effect…

A medical research team conducted a study to test the effect of a cholesterol reducing medication.  At the end of the study, the researcher found that of the 4700 people who took the medication, 301 died of heart disease.  Of the 4300 people who took a placebo, 357 died of heart disease.  At 0.05 significance level, can you conclude that the death rate is lower for those who took the medication than for those who took the placebo? The following hypotheses were set:

The heights of fully grown white oak trees are normally dist…

The heights of fully grown white oak trees are normally distributed with a mean of 90 feet and standard deviation of 3.5 feet.  A sample of 16 fully grown white oak trees is selected. Which of the following is true about the shape of the sampling distribution of the sample means?

An educator is interested to test whether the SAT preparator…

An educator is interested to test whether the SAT preparatory course is effective in raising the SAT scores.  A simple random sample of 7 students took SAT, and their scores are recorded below.  The same students took SAT after the preparatory course.  At 5% significance level, is there an increase in SAT scores after the preparatory course?  Assume that both distributions of SAT scores before and after the preparatory course are normal.  Find the corresponding p-value (use a calculator)