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A researcher is curious to see if the amount of time spent on social media influences how often friends meet in person to socialize.  After their sample is selected the researcher tells half the sample to spend at least 4 hours each day on social media and the other half to spend no more than 4 hours on social media each day.  Then to report back at the end of the month how many times they meet in person with their friends to socialize.  What type of study design is this?

According to the Chicago Cubs there average attendance at a home game through out the year of 2019 was 38,208 based on attendance at all home games in 2019.  38,208 is a parameter.

It is known that people in the USA spend on average 17 hours a day using electronic devices with a standard deviation of 7 hours. This data follows a normal distribution. What is the probability someone spends more than 20 hours using electronic devices a day? (round your answer to 4 decimals)

Based on the following research question: Is someone more likely to lose weight because they go to they gym at least 4 days per week?   The variable amount of weight lost [answer1] The variable go to the gym at least 4 days a week [answer2]

It is known that people in the USA spend on average 15 hours a day using electronic devices with a standard deviation of 4.75 hours. This data follows a normal distribution. What is the probability someone spends more than 13 hours using electronic devices a day? (round your answer to 4 decimals)

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