The students are______the HINl flu. [ ]
A. talking about
B. talking at
C. talking with
答案:A
O为坐标原点,正△OAB中A、B在抛物线y2=2x上,正△OCD中C、D在抛物线y=2x2上,则△OAB与△OCD的面积之比为______.
石棉引起的法定职业肿瘤为()。
A.白血病
B.直肠癌
C.肺癌
D.间皮瘤
E.肺癌、间皮瘤