To find the frictional force offered by the ground
\(v=u+a t\)
\(v=0\)
\(0=8-\mu g(10)\)
\(\mu=\frac{8}{100}=0.08\)
To move the body with constant velocity on this surface, internal force applied should be equal to friction force \(F=\mu m g\)
\(=(0.08)(1)(10)=0.8\,N\)