To move the body withconstant velocity on this surface, INTERNAL force applied should be equal to friction force
F = mg
= (0.08)(1)(10)
= 0.8N
answer2---mass=1kginitial velocity`u`=8m/sfinal velocity`v`=0m/stime=10 sec.therefore, acceleration=v-u/t =0-8/10 =-0.8m/s^2Force=mass*acceleration =1*(-0.8) = -0.8NWe know that force cannot be in negative therefore, force applied =0.8N