How does the author use paragraphs 30-31 to refine their ideas? Cite evidence in your answer.

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.        

it continues in business

because this was the year that the state of israel was formed

there are indirect ways of affecting state laws   by with holding funding's. and that's why we have a 55mph speed on the high way with a design of 70mph speed.