1. Data from various public electricity supply authorities was collected.

The data include the following variables:

X1, the capital costs,

X2, the labor costs,

X3, the energy costs.

Y, the output of electricity in millions of kilowatts,

We will estimate a model of the form: Y = A0 + A1 * X1 + A2 * X2 + A3 * X3.

Given below is the regression output

SUMMARY OUTPUT Regression Statistics Multiple R 0.210124 R Square 0.044152 Adjusted R Square 0.05481 Standard Error 610.4604 Observations 16 ANOVA Significance Of 5S MS F F Regression 3 206566.6 68855.54 0.184767 0.904708 Residual 12 4471943 372661.9 Total 15 4678510 Standard Upper Coefficients Error t Stot P-value Lower 95% 95% Intercept 287.8562 291.8021 0.986478 0.343372 -347.926 923.6383 X1 -0.65164 3.062604 -0.21277 0.835074 -7.32449 6.021195 X2 119.6728 557.4253 0.214689 0.833615 -1094.85 1334.198 X3 -2.09825 13.87221 -0.15126 0.882287 -32.3232 28.12669