A census is a regularly-occurring and official count of a particular population. Census data available at the United States Census Bureau website are an example of: Private information Private behavior Public behavior Public information According to the federal regulations, which of the following studies meets the definition of research with human subjects? A study of twenty 4th grade classrooms in which researchers ask the schools to systematically vary the time of day reading is taught, and collect weekly assessments of reading comprehension for each child over a three-month period. An analysis of aggregate data comparing statewide high school graduation rates provided by the State Department of Public Instruction, using county tax information. A feasibility study for implementing a year-round school program, focusing on economic issues such as facilities utilization and transportation costs. The collection of data, by a playground designer hired by the superintendent of schools, about the physical dimensions of school playgrounds, presence of fencing, and the kinds of equipment currently provided. According to the federal regulations, human subjects are living individuals about whom an investigator conducting research obtains information through interaction or intervention with the individual, and uses, studies, or analyzes the information; or: Obtains, uses, studies, analyzes, or generates identifiable public information. Observes public behavior. Obtains