A man is running around a circular track that is 200 m in circumference. An observer uses a stopwatch to record the runner's time at the end of each lap, obtaining the data in the following table.

Time Distance (m)

39 200

79 400

128 600

190 800

255 1000

321 1200

391 1400

462 1600

a) What was the man's average speed (rate) between79s and190s? (Round your answer to two decimal places.)

m/s

b) What was the man's average speed between321s and462s? (Round your answer to two decimal places.)

m/s

(c) Calculate the man's speed for each lap. Is he slowing down, speeding up, or neither?

slowing down

speeding up

neither