What is the for the multiple linear regression model? (Report to 4 decimal places)

Step 4: Make a decision and draw a conclusion

The decision rule is to:

Next predict the child’s height in centimetres with the same values for mumheight and hhincome, but with rainfall equal to two standard deviations below the sample average.

What is the predicted height? (Report to 1 decimal place and include appropriate units)   

Step 4: Make a decision and draw a conclusion

The decision rule is to:

Given the range of values we get here, what can we say about the practical significance of rainfall at birth in determining a child's height?

(Hint: You may want to compare the range of values you get with the sample standard deviation for childheight.)