1.The coefficient of static friction between the m = 2.90 kg crate and the 35.0° incline of Figure P4.41 is 0.340. What minimum force vector F must be applied to the crate perpendicular to the incline to prevent the crate from sliding down the incline? 2.A box of books weighing 250 N is shoved across the floor of an apartment by a force of 360 N exerted downward at an angle of 34.9° below the horizontal. If the coefficient of kinetic friction between box and floor is 0.57, how long does it take to move the box 3.80 m, starting from rest? 3.Objects with masses m1 = 8.0 kg and m2 = 4.00 kg are connected by a light string that passes over a frictionless pulley as in Figure P4.30. If, when the system starts from rest, m2 falls 1.00 m in 1.70 s, determine the coefficient of kinetic friction between m1 and the table. Desperately need help dont have a clue what to do.