Things are going pretty well for George (see item 26) until he jumps from reinforcing every tenth response to reinforcing every 50th response. At this point, the pigeon responds erratically and nearly stops responding entirely. George's pigeon is suffering from .

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. 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. a feasibility study for implementing a year-round school program, focusing on economic issues such a facilities utilization and transportation costs. an analysis of aggregate data comparing statewide high school graduation rates provided by the state department of public instruction, using county tax information.

What impact does geography have on where people live in brazil?

Which group earned 19 medals of honor as a result of its efforts in the wars against native americans in texas?