A school district is comparing two reading programs for high school students who are reading below grade level. Two schools with very similar student bodies are used to test the programs, with a different program being used at each school. Identify the threat to internal validity described in each scenario that might occur in this study.

Governor reagan: mr. ellis, i think this idea that has been spawned here in our country, that inflation somehow came upon us like a plague and therefore it's uncontrollable and no one can do anything about it, is entirely spurious, and it's dangerous to say this to the people. when mr. carter became president, inflation was 4.8 percent, as you said. it had been cut in two by president gerald ford. it is now running at 12.7 percent. president carter also has spoken of the new jobs created . . but that can't hide the fact that there are 8 million men and women out of work in america today, and 2 million of those lost their jobs in just the last few months. mr. carter had also promised that he would not use unemployment as a tool to fight against inflation. and yet, his 1980 economic message stated that we would reduce productivity and gross national product and increase unemployment in order to get a handle on inflation, because in january, at the beginning of the year, it was more than 18 percent. which reasons and evidence does reagan use to support his argument? check all that apply. (1) the gross national product in 1979 (2) the gross national product in 1980 (3) the decrease in inflation rates (4) the increase in inflation rates (5) the number of jobs lost (6) the number of jobs created