<PRE><B>Question 983320</B>
.
Since AB and CD are parallel, angles B and C are supplementary, so:
4x degrees + 2x degrees=180 degrees
6x degrees=180 degrees
x=30 degrees
.
Opposite angles of a parallelogram are congruent so angle B is congruent to angle D, so:
measure of angle B=4x degrees
measure of angle D=y
angle B=angle D
4x=y (x=30 degrees from above)
4(30 degrees)=y
120 degrees=y
ANSWER: (a.) 120 degrees</PRE>