Use the figure to find the measures of the numbered angles please also include a step by step explanation

1. there are 25 students who started computer programming in elementary school and 25 students who started computer programming in middle school. the first group had a mean final project grade of 95% and the second group had a mean final project grade of 92%. the line plot shows the differences after 10 rerandomizations. determine whether the difference in the means of the two groups is significant based on the line plot. explain your answer.

Aline has a slope of 1/4 and passes through point (0.4,-1/2). what is the value of the y-intercept?

Ineed with math stuff it involves graphs