Public health researchers launched a study to assess what particular social behaviors increase the risk of acquiring COVID-19. They included healthy adults 60 years or older living in all independent communities in North Fulton, Georgia. The study period included March-April 2020. What type of study population is this? Question 3 options: a) Dynamic Population b) Fixed Population c) Catchment Population d) Candidate Population

The Federal Bureau of Investigation (FBI), as part of its internal security mission, serves as a database for all the reported crimes committed in the United States. One question that might be of interest is does having more police officers reduce the number of homicides? To investigate this claim, the 2013 data from the twenty largest municipal cities was supplied by the FBI's Uniform Crime Report. Below are two observations from the dataset: > head (cities) City Pop Homicides Police Density MedHome Mayor 1 New York 8175.133 335 4.2595 27016.30 5.5390 1 2 Chicago 2695.598 414 4.4309 11843.58 1.8310 The variables included in the study are: Name of city Population of city in 1,000s of people Number of homicides in the year 2013 Number of police officers per 1,000 people Number of people per square mile Median home price in $100,000 1 if city has a "Strong Mayor" form of government; 0 if not City Рор Homicides Police Density MedHome Мayor Model: log(u;) = Bo + B1Police; + B2MedHome; +…

Vitamin​ D, whether ingested as a dietary supplement or produced naturally when sunlight falls upon the​ skin, is essential for​ strong, healthy bones. The bone disease rickets was largely eliminated during the​ 1950s, but now there is concern that a generation of children more likely to watch TV or play computer games than spend time outdoors is at increased risk. A recent study of 2900 children randomly selected found 24​% of them deficient in vitamin D. Complete parts a through c below.   ​a) Construct a​ 98% confidence interval for the true proportion of children who are deficient in vitamin D. Select the correct choice below and fill in any answer boxes within your choice.     A. enter your response here,enter your response here ​(Round to three decimal places as​ needed.)   B. The conditions of a confidence interval are not satisfied. Part 2 ​b) Explain carefully what the interval means.     A. We are​ 98% confident that the proportion of people deficient in…

Plastics which are no longer needed for current use end up being recycled, or incinerated, or discarded into landfills or the natural environment. According to the 2016- 17 Australian Plastics Recycling Survey, the term ‘recycling’ is used in the plastics industry “to cover a range of activities including collection, sorting, reprocessing, export for reprocessing and manufacture of new products.” In order to avoid double-counting materials, survey data is typically collected on the reprocessing stage, which is the stage where waste plastics are converted into a new product (may be finished or semi-finished).