A woman at an airport is towing her 17.0 kg suitcase at constant speed by pulling on the strap at an angle of θ above the horizontal (Fig. P4.40). She pulls on the strap with a 26.0 N force, and the friction force on the suitcase is 10.0 N. What angle does the strap make with the horizontal? What normal force does the ground exert on the suitcase?