In an experiment, a rat can choose between hitting a blue button (which provides a snack) or a yellow button (which provides a shock). in each round of the experiment, the buttons may or may not switch colors. this experiment combines elements of which two researchers?

Donder and Skinners

Explanation:

Donder and Skinner both were behavioral psychologists. They both work on the experiment related to rat learning of behavior. This experiment deals with the response and positive reinforcement. Skinner theory was on ope-rant conditioning and conduct many experiments on animals like a rat. He used a box in his experiment that is called the Skinner bore experiment. The experiment deals with and even show the positive reinforcement. Francis Donder was an ophthalmologist. He worked on subtraction and reaction time measurements in his experiment. He also wants to study the reaction time of subtraction in the rat and functioning of the frontal lobe so he contributes with Skinner in his experiment. They work together in that experiment.

it should be d or b but i'm sure it's d

i believe the answer is: returns on investments, no wages

people who belong in upper class society would most likely get there by obtaining multiple source of income, which a certain percentage of ownership for businesses. since most of them are job creator, they would most likely get their money from profit, not wages.