函数f(x)=x3+x的图像在x=1处的切线方程为[ ]
A．4x-y+2=0
B．4x-y-2=0
C．4x+y+2=0
D．4x+y-2=0
答案：B
Scott usually gets up at 6:10, then he cleans _______ room. [ ]
A. he
B. his
C. him
D. himself
下列哪项不是疾病地区分布形式（）
A.城乡分布
B.国家间分布
C.大流行
D.国家内分布
E.地方性
