Answer
Age: The results are ambiguous. We can conclude that $µ_{40~or~older}\neµ_{20-29}$, but we could not conclude that $µ_{40~or~older}\neµ_{30-29}$ or that $µ_{30-39}\neµ_{20-29}$.
There is at least one Type II error (when we do not reject $H_0$ when we should have rejected).
Mixture: $µ_{Diet~3}=µ_{Diet~2}\neµ_{Diet~1}$
Work Step by Step
With the results from item (b) still available:
Select Stat -> ANOVA -> General Linear Model -> Comparisons
In Response select Birth Weight (g). In Type of comparison select Pairwise. In Method select Tukey. In Choose terms for comparisons select Age and Diet.
Click OK.
