Which type of matter is always made up of only one kind of atom? (A) compound
(B) element
(C) mixture
(D) molecule

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:

The first national government for the united states was

Push-and-pull factors contribute to