原发性肝癌的死亡率在消化系统恶性肿瘤中列（）。
A.第一位
B.第二位
C.第三位
D.第四位
E.第五位
参考答案：C
在匀强电场中将一个带电量为q、质量为m的小球由静止释放，小球的运动轨迹为一直线，此直线与竖直方向的夹角为θ，则匀强电场E的最小值是（ ）
A．mgq
B．mg•sinθq
C．mg•cosθq
D．mg•tanθq
“When the stars threw down their spears,And water’ d heaven with their tears,Did he smile his work to seeDid he who made the Lamb make thee ”Questions:A. Who’s the poet of the quoted stanza, and what’s the title of the poemB. Whom does the “he” refer toC. What does the “Lamb” symbolize
