Assuming there are 4 sample points for linear regression modelling, and the real output values for these 4 points are y1=24,y2=45,y3=116,y4=156, respectively. After data fitting, we get the predicted output values for these four points as 22,44 , 114 , and 160 , respectively. How much of the Root Mean Square Error (RMSE)? 2.5 6.25 25