Please help!! A mathematics software company claimed that their software could increase student performance in Algebra 2 by 30 points. In a random sample of 25 students who used the software, the average was 21 points, and had a standard deviation of 12 points. What is the z-value? Do we accept or reject the claim based on the z-value? Explain.

3x + 4y = 5 x- 3y = -7 solve by substitution

Determine which postulate or theorem can be used to prove that lmn =nmo

For a science project, a high school research team conducted a survey of local air temperatures. based on the results of the survey, the found that the average temperatures were around 10 degrees higher than expected. this result was wrong. the trouble with the survey was that most of the locations were exposed to direct sunlight and located over asphalt or sand, which resulted in higher temperatures than normal. this is a classic example of an error in which phase of inferential statistics?