Contact us
Choose a category below so we can get back to you as quickly as possible.
甲行完全程需要12÷4/5=15小時 相遇時間1÷(1/15+1/12)=20/3小時 甲行了45×20/3=300千米
We and our partners use cookies and other technologies to analyze traffic and optimize your experience. View more info and control your cookies settings at any time in our Cookies Policy.