**1. A truck hauls a trailer at 60 km/hour when exerting a steady pull of 600 N. If the work is done for 40 minutes, the power required is**

(a) 6 kW

(b) 4 kW

(c) 2.4 kW

(d) 10 kW

**2. Two blocks A and B of 1 kg each are kept on a flat surface, one above other. The coefficient of friction between each contacting pair is 0.2. If the lower block is pulled with a horizontal force F, the minimum value of F for which the slip occurs between the blocks is nearly**

(a) 5.9 N

(b) 4.9N

(c) 18.4N

(d) 0