71. Two-dimensional bin packing refers to the problem of packing rectangles of various sizes into a minimum number of rectangles, with the sides of the packed rectangles parallel to those of the containing rectangle.
71.
(a) Answers will vary.
(b) Answers will vary.
(c) Packing rectangles of width 1 in an rectangle is a special case of the two-dimensional problem.
(d) Answers will vary.