(A) When two dice are thrown,the sample space $S$ is given by $S = \{(x, y) : x, y \in \{1, 2, 3, 4, 5, 6\}\}$.
Event $A$ is defined as getting an even number on the first die. Thus,the first coordinate $x$ must be $2, 4,$ or $6$.
$A = \{(2, 1), (2, 2), (2, 3), (2, 4), (2, 5), (2, 6), (4, 1), (4, 2), (4, 3), (4, 4), (4, 5), (4, 6), (6, 1), (6, 2), (6, 3), (6, 4), (6, 5), (6, 6)\}$.
Event $B$ is defined as getting an odd number on the first die. Thus,the first coordinate $x$ must be $1, 3,$ or $5$.
$B = \{(1, 1), (1, 2), (1, 3), (1, 4), (1, 5), (1, 6), (3, 1), (3, 2), (3, 3), (3, 4), (3, 5), (3, 6), (5, 1), (5, 2), (5, 3), (5, 4), (5, 5), (5, 6)\}$.