Need explantions

12. An educational researcher is analyzing the test scores for physics students taught using two different methods - a traditional method, and a web-based self-paced method. Can he conclude, at a =.05, that the test scores in the web-based self-paced method are lower? Traditional Web-based Self-paced Sample size 50 70 Mean test score 80 77 Population variance 24 34 13. Test the significance of the correlation coefficient r at a = 0.05 for the data below. X values 41 48 53 63 70 Y values 97 102 112 119 128 14. Compute the standard error of the estimate for the data below. Round to the thousandths place. X 25 26 27 28 29 30 y 82.26 83.14 84.44 86.44 88.86 91.1415. A survey of 500 recent degree recipients found that 97 received associate degrees; 281, bachelor degrees; and 122, graduate degrees. Is there enough evidence to conclude that the proportions in the survey differ from a report that 23.3% were associate degrees; 51.1%, bachelor degrees; and 25.6% were graduate degrees? Use or = 0.025