please assist me in understanding a-1.

The following table lists a portion of Major League Baseball's (MLB's) leading pitchers, each pitcher's salary (In $ millions), and earned + MLB_Pitchers Sheet2 run average (ERA) for 2008. Salary ERA J. Santana 16.0 2.32 Salary ERA C. Lee 2.0 2.31 J. Santana 16.0 2.32 C. Le 2.0 2.3 C. Hamels 0.3 2 . 85 T. Lincecum 0.1 2.01 C. Sabathia 9.0 2.19 Click here for the Excel Data File R. Halladay 4.0 2.22 J. Peavy 5.4 2.31 D. Matsuzaka 8.1 2.34 a-1. Estimate the model: Salary = So + 1ERA + E. (Negative values should be indicated by a minus sign. Enter your answers, in R. Dempster 5.7 2.03 millions, rounded to 2 decimal places.) B. Sheets 11.3 2.53 C. Hamels 0.3 2.85 Salary = -0.14 + 6.52 ERA