The president is elected to serve for how many years?

answer; i believe that the correct answer is ; the eastern and western churches spoke different languages;

answer; for children with two myopic parents,the likelihood of becoming myopic is ) correlated with the number of hours spent playing sports each week;

answer; i believe the above is (false)

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.