An electron moves in the positive x-direction a distance of 2.31 m in 2.99-10'8 s, bounces off a moving proton, and then moves in the opposite direction a distance of 1.69 m in 3.39-10'8 s. a) What is the average velocity of the electron over the entire time interval? 9.718x105 m/s You are correct. Your receipt no. is 1613035 W b) What is the average speed of the electron over the entire time interval? 5.731E7m/s Submit Answer You have entered that answer before Incorrect. Tries 5/99 Previous Tries The 2009 world record for the men's 100-m dash was 9.58 s. The third-place runner crossed the finish line in 9.84 5. When the winner crossed the finish line, how far was the third-place runner behind him? a) Compute an answer that assumes that each runner ran at his average speed for the entire race. 5.73m Submit Answer Incorrect. Tries 3/99 Previous Tries b) Compute another answer that assumes, that after an initial acceleration phase, world-class sprinters run at a speed of 12.0 m/s. If both runners in this race reach this speed, how far behind is the thirdplace runner when the winner finishes