Perform the following steps to predict values with multiple regression:

1. Fit a linear model with the income, prestige, and women variables:

        > model = lm(income ~ prestige + women, Prestige)  

2. Assign values to be predicted into newdata:

        > newdat = data.frame(prestige = c(75,80), women=c(14,13))

3. Compute the prediction result using the confidence interval with level set as 0.95:

        > predict(model, newdata = newdat)
        Output:
            1        2 
        12194.80 13072.56 
  

Compute the prediction result using this prediction interval:

> predict(model, newdata = newdat, interval="predict")
Output:
    fit      lwr       upr
1 12194.80 6994.903 17394.69
2 13072.56 7847.050 18298.06