23. What provides autos with electric power in an automated highway system? (A)) A rail. (B)) An engine. (C)) A retractable arm. (D)) A computer controller.

31. “... Old is suddenly in” (Line 1, Para. 1) most probably means “________”. (A)) America has suddenly become a nation of old people (B)) gerontology has suddenly become popular (C)) more elderly professors are found on American campuses (D)) American colleges have realized the need of enrolling older students