Which of these events happened in the 20th century?

One common educational practice is to chart students' progress over time so that students can see their own improvement. these progress charts often lead to higher student achievement in the absence of other observable forms of reinforcement. the effectiveness of such charts in changing behavior illustrates the role of reinforcement as:

Which of the following statements about slavery is not correct? a. slavery was a very profitable industry that build the united states. b. the french were the first to profit from the african slave trade. c. slaves were sold at auction blocks like farm animals. d. slaves were not considered citizens or even people.

Essay: both benedict arnold and alexander hamilton were ambitious men who took great risks as leaders in the american revolution. write an essay in which you discuss the impact that the ambitions of individuals had on the birth of the united states. remember to use textual evidence from both written sources to support your argument.