On a day when the air is still a windmill still possesses

this null effect is caused by a weak manipulation and ineffective internal validity. in a scientific study, as the one dr. morimoto is trying to perfom, internal validity refers to the confidence placed in the cause-effect relationship and to how well an experiment is done and able to eliminate confounding variables.        

the economic difference between the three colonial regions. shipbuilding, whaling, fishing, and trapping where also main factors to the economy. the southern regional colonies economy was based on sugarcane, rice, cotton, tobacco, and indigo.