In the figure, A B C D is a rectangle and E F G H is a parallelogram. Using the measurements given in the figure, what is the length d of the segment that is perpendicular to \overline{H E} and \overline{F G} ?
Answer Choices
A. 6.8
B. 7.1
C. 7.6
D. 7.8
E. 8.1