---John always thinks of others instead of himself
---So he does. It is_____of him to want to help others

A．aggressive

B．evident

C．typical

D．conventional

If the radius(半径) of circle  Ⅲ in the figure3(图3) is  of the radius of circle Ⅱ,and the radius of circle Ⅱ is  of the radius of circle Ⅰ,then the area of the shaded region iswhat part of the area of circle Ⅰ?(    )

(A);  (B);(C);(D)

 

Suppose that in Fig.2，the length of side of square ABCD is 1，E and F are mid-points of CD and AD respectively，GE and CF intersect at a point P．Then the length of line segment CP is．（英汉词典：figure（缩写Fig．）图；length 长度；square 正方形；mid-point中点；intersect 相交；line segment 线段）