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Based on the following research question: Does having diabetes lead to people increasing the average number of servings of fruit they normally eat per day?   The variable average number of servings of fruit eaten per day is the [answer1] The variable having diabetes is the [answer2]

A researcher is curious to see if the amount of time spent on social media influences how often friends meet in person to socialize.  The research obtains 100 participates who met with their friends in person at least 15 times in the last month to socialize and 100 participates who met with their friends in persons less than 15 times in the last month to socialize.  Then the researcher asks the participants on average how many hours per day did they spend on social media during the month before.  What type of study design is this?

Based on the following research question: Is an interest in playing video games caused by being introduction to STEM fields at an early age?   The variable do you play video games [answer1] The variable age introduced to STEM fields [answer2]

4 students apply to a PhD program.  The program accepts 45% of all applicants.  Students are accepted and rejected independently of each other.  Let the random variable X represent the number of the 4 students who get accepted into the PhD Program.   What is the probability that 2 students are accepted to the program if it is known that more than 1 will be accepted? (round your answer to 4 decimal places)  (Hint: Binomial distribution with P=45% and n=4, and conditional probability)

The probability that a person tested negative on a screening test given that he/she does not have a disease is called the

When the sample is selected by using subjects that are most easily contacted, what type of sampling is being done?

It is known that people in the USA spend on average 16 hours a day using electronic devices with a standard deviation of 3.5 hours.  This data follows a normal distribution. What is the probability someone spends exactly 16 hours using electronic devices a day? (round your answer to 4 decimals)

A pediatrician would like to study cholesterol level in children 2 to 6 years of age. He selected 5 patients and found their cholesterol levels to be: 185, 225, 250, 196, 179 The sample standard deviation of cholesterol level of this group of patients is? round your answer to 4 decimal places.

A sample of 2500 patients were taken to assess a medical test.  40% of the sample had a positive test, 563 patients have the disease and tested negative, and 235 patients do not have the disease and tested positive. What is the probability someone has a negative test if it is known they do not have the disease?  (round your answer to 4 decimal places)

Using the information below calculate the predicted value for Y for the given value of X. Y (Dependent Variable) = Cost of a car in thousands of dollars (i.e. Y = 1 means one-thousand dollars) X (Independent Variable) = Miles per Gallon in city traffic   yhat = 28.1 + 0.62*X   On average how many thousands of dollars would a car cost if it gets 30 Miles per Gallon in city traffic (round your answer to 4 decimal places)?