Q. A weight of 4.9 N rests on a rough horizontal floor that has a coefficient of friction of 0.5. If g = 9.8 m/s2, the smallest horizontal force that gives the weight an acceleration of 4m/s2 is most nearly

• (A) 2.5 N
• (B) 3 N
• (C) 2 N
• (D) 4.5 N