21.   Asked about the discrepancy, Markman said he had no explanation for why any one group would perform better than another.

22.   Astronomers last year reported that the Hubble Space Telescope may have detected signs of the gas, but some say say that data could have other explanations.

23.   Astacio, frustrated by his first stint on the disabled list in his nine-year career, said he has no explanation for his continuing shoulder problems.

24.   Astronomers think they have an explanation.

25.   At the same time, White House officials have specific explanations for why airlines and insurers should be granted exceptions to the rule.

26.   Babcock had no explanation for that.

27.   Badu, however, has another explanation for the interest.

28.   Because of those doubts, engineers hold open the possibility that the collapse had other explanations, like damage caused by falling debris or another source of heat.

29.   Bookman had no explanation for the decline.

30.   Boston defense attorney Andrew Good said Friday he had no explanation for how the defense medical experts might have missed the possibility that baby Eappen was strangled.