题目

如图，一次函数y＝kx＋b的图象与x轴、y轴分别相交于A，B两点，⊙O经过A，B两点，已知AB＝2，则的值为________． 答案：－After several years of observation, the research group ______ the conclusion that language acquisition isfaster when students ______ to the situation where it is spoken. [     ]A. has come to; expose              B. have arrived at; are exposed C. has concluded; are exposed        D. have reached; expose