1.   None of these investigations has produced convincing answers to the mystery of the triangle, but there is no shortage of interesting theories.

2.   And with a deadline looming, nobody yet seems to have put forward a convincing answer.

3.   But few if any offer convincing answers to the question of why so many children find reading so difficult that they never learn.

4.   But no one is offering worried residents a convincing answer as to whether the low levels of the substance poses a threat to their health.

5.   But no one is offering worried residents a convincing answer about whether the low levels of the substance poses a threat to their health.

6.   Castro and officials of the Texas Low-Level Radioactive Waste Disposal Authority have convincing answers for most questions raised by critics.

7.   Factual questions linger with no convincing answers.

8.   His spirited presentation and the enthusiastic crowd reaction offered a fairly convincing answer to journalists who keep whining that Gore is dull and colorless.

9.   The State Department is still working on that one, and no one expects it to have a convincing answer any time soon.

10.   Two women, Yvonne Trevino of Peoria and Mia St. John of Los Angeles, hope to provide a convincing answer today in different cities and on competing networks.