Open Question: PROBLEM solving????

A runner, competing in the 1500 m event, has completed the first 1000 m in 2 minutes 50 seconds. Q1. At what average speed will the runner need to run the final 500 m to complete the race in exactly 4 minutes? Q2. At what average speed will the runner need to run the final 500 m to have an average speed for the whole 1500 m of a) 6 m/s b) 6.4 m/s c) 7 m/s d) 8 m/s Q3. Can the runner have an average speed of 9 m/s for the entire 1500 m? Explain your answer. Hint. Remember the definition of speed