2.x is also related to time.

Multiple choice

3.a I think both B and C are equal, so I choose A, and I estimate that there is something wrong with the topic, which should be the circumference of a semi-circle.

solve problems

1. The circumference should be 3.768m.. (2000/3.768)/200=3 (integer reserved)

4. The distance between them is 90+30 * 3.14 =184.2m..

182.4/(315-275) = 4.56 minutes.