函数 f(x) 在[a, b]上有界是函数 f(x) 在[a, b]上可积的
A. 必要非充分条件
B. 充分非必要条件
C. 充分必要条件
D. 既不充分, 也不必要条件
Fill in the blank with the following transitional words. (in contrast, consequently, instead, what is more, first, second, instead)European universities and universities in the United Statesstates are different in many ways. , European students enrollin fewer courses each term than the United States studentsdo. , most European courses are given byprofessorswho lecture to their classes. , unitedstates professors often ask their students questions orallow their students do dorm discussion groups. , they ask students to write more papers than the European professors do., European students' final examinations are usually oral., American students take written final examinations. , a European university is mainly a place to study in, whereas at most United States universities , social activities take up a large part of th students' time.