About 25 years ago I was teaching lots of large classes which required multiple choice tests. I always went over the questions and answers with the whole class after the test. From that I learned that despite the writer's intention, it is nigh impossible to write 30 questions for which there is only one credible answer, if you take the time to listen to the rationale of those who answered differently than the writer intended.

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1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13