Question 1: When A and C meet, the distance between them is the sum of the distances that B and C retreat from each other, that is, (60+70) × 2 = 260 (meters). When Party A and Party C meet, they are 260 meters apart, so it takes 260 \ time from the beginning to the meeting with Party A and Party C, and the distance between Party A and Party B is (50+70) × 26 = 3 120 (meters). Question 2: 5 minutes late, 60 × 5 = 300 meters less, 2 minutes early, 75 × 2 = 150 meters more. The exact arrival time is (300+65438+). Xiao Wang: 4 km/h Xiao Zhang: [6× (40× 3 ÷ 60)-2] ÷ 2 = 5 (km/h) Xiao Wang: (6+40× 3 ÷ 60) ÷ 2 = 4 (km/h) Question 4.