load('gas.Rdata')
gaslm <- lm(gas$Gas ~ gas$Temp * gas$Insulate2)
summary(gaslm)

## 
## Call:
## lm(formula = gas$Gas ~ gas$Temp * gas$Insulate2)
## 
## Residuals:
##      Min       1Q   Median       3Q      Max 
## -0.62020 -0.18011  0.03405  0.16379  0.59778 
## 
## Coefficients:
##                        Estimate Std. Error t value Pr(>|t|)    
## (Intercept)             6.85383    0.11362  60.320  < 2e-16 ***
## gas$Temp               -0.39324    0.01879 -20.925  < 2e-16 ***
## gas$Insulate2          -2.26321    0.17278 -13.099 4.71e-16 ***
## gas$Temp:gas$Insulate2  0.14361    0.04455   3.224  0.00252 ** 
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Residual standard error: 0.2699 on 40 degrees of freedom
## Multiple R-squared:  0.9359, Adjusted R-squared:  0.9311 
## F-statistic: 194.8 on 3 and 40 DF,  p-value: < 2.2e-16