[问答题]
Water waves having parallel crests 264gn.tri fqt8q cb0f2.59c phn9 yevv66 cm apart pass through two openings 5.0 cm apart in a board. At a point 2.0pvev6 96ych9n m beyond the board, at what angle relative to the “straight-through” direction would there be little or no wave action?
