Answer:
1210 N/m between the inner and outer edges (repulsive)
252.59 N/m between inner and line charges (attractive)
1210+252.59=1462.59 N/m effective force/metre on the inner edge
Explanation:
f=k*Qq/r^2 was applied, the charges are concentrated at the edges of a ring both inner and the outer were shape edges with uniform charge densities 6.6 micro C/m of distance 4.5-2.7=1.8 cm