After they had failed the writing exam that was required of all students before graduation, fifteen students were placed in a class in which they received additional tutoring. After completing this class, all fifteen students retook the exam and earned higher scores. Their success was held up as an example that the class curriculum really works. What source of internal invalidity has not been considered?

When something is moving, it is in motion. pressing the gas pedal in a car will put the car in motion. two important properties of motion are speed and direction. speed is how fast an object is moving. tony and tanya both run for the same amount of time, in the same direction. tanya runs much further than tony in that time. how does tony's speed compare to tanya's speed? a) their speed is equal. b) tony is slower than tanya. c) tony is faster than tanya. d) without a stopwatch, you can't say for certain.

Explain the term minorities ? why do they lag behind the majority community both educationally and economically ? how can they get their rightful place in society

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.