In a regression analysis involving 30 observations, the following estimated regression equation was obtained. If required enter negative values as negative numbers.

1. Interpret b1, b2, b3, and b4 in this estimated regression equation (to 1 decimal). Assume that for each coefficient statement, the remaining three variables are held constant. Enter negative values as negative numbers.
   
   b1 =  estimated change in y per 1 unit change in x1
   b2 =  estimated change in y per 1 unit change in x2
   b3 =  estimated change in y per 1 unit change in x3
   b4 =  estimated change in y per 1 unit change in x4
   
   
2. Predict y when x1 = 10, x2 = 5, x3 = 1, and x4 = 2 (to 1 decimal).
   
    

= 17.6 + 3.8x, - 2.3x2 + 7.6x3 + 2.7x.