. Determine whether the forces in the pair are pulling at right angles to each other. For each group of three forces below, determine whether the forces in each pair are pulling at right angles to each other. 13 lb, 35 lb, resultant force 30 lb no; 20 lb, 15 lb, resultant force 25 lb yes 13 lb, 35 lb, resultant force 30 lb yes; 20 lb, 15 lb, resultant force 25 lb yes 13 lb, 35 lb, resultant force 30 lb yes; 20 lb, 15 lb, resultant force 25 lb no 13 lb, 35 lb, resultant force 30 lb no; 20 lb, 15 lb, resultant force 25 lb no