pls help me out asap thanks provide solution

1. Two planes start out 2800 km apart and move towards each other meeting after 3.5 hours. One plane fly at 75 km/hour slower than the other plane. What was the speed of each plane? Ans: speed of the planes: 437.5 km/hr & 362 km/hr 2. John can paint a house in 28 hours. John and Dave can paint the house in 17 hours working together. How long would it take Dave to paint the house by himself? Ans: time = 43.2727 hours 3. We want to fence in a field whose length is twice the width and we have 80 feet of fencing material. If we use all the fencing material what would the dimensions of the field be? Ans: width = 13.33 ft & length = 26.66 ft