Chapter 2.4, Problem 34E

Compute each of these double sums.

   ${\displaystyle \underset{i=1}{\overset{3}{\sum }}{\displaystyle \underset{j=1}{\overset{2}{\sum }}\left(i+j\right)}}$

   ${\displaystyle \underset{i=0}{\overset{3}{\sum }}{\displaystyle \underset{j=0}{\overset{2}{\sum }}\left(3i+2j\right)}}$

   ${\displaystyle \underset{i=1}{\overset{3}{\sum }}{\displaystyle \underset{j=0}{\overset{2}{\sum }}j}}$

   ${\displaystyle \underset{i=0}{\overset{2}{\sum }}{\displaystyle \underset{j=0}{\overset{3}{\sum }}{i}^2{j}^2}}$