Anyone help me with these last few clues - 17a. (5) 30.0 - 39.9 on the BMI scale, 18d. (9) Partical first photographed by Wilson Bentley in 1885, 28a. (10) One of the four houses of Hogwarts with students including Harry Potter and 39a.(3,4) The -------, a popular single panel comic strip by Gary Larson. I expect I am the only person not to know about Harry Potter. Many thanks.