Below is a data for rainfall and runoff volume in Marfa Texas Rainfall 12 14 17 23 30 40 47 Run off 4 10 13 15 15 25 27 26 Rain fall 55 67 72 81 96 112 127 Run off 38 46 53 70 82 99 100 a. Build a linear regression model. b. Find the residual of all the data points. What is the average value of these residuals? What is the average value of the residuals squared? c. What is the total variance of the runoff volume? What proportion of the observed variation of runoff volume can be attributed to the linear relationship between rainfall and run off?

Enter a set of parentheses to make the equation =-8    6+3•2-4/2•5+8

I want all solved please thanks for first 3

Since the first question has been solved, please solve the second question. Thank you!

A test contains 12 problems. The teacher gives 24 points for each correctly solved problem and withdraws 15 points for incorrectly solved problems. If a problem is not solved it is considered incorrect.   Ron claims he got a zero for the test. That is impossible says Mia. Is there any reason for mia to say that?