Contact us
Choose a category below so we can get back to you as quickly as possible.
質量、重力、力、長度四個選項中的質量和長度只有大小沒有方向,重力、力既有大小又有方向,符合題意.故選B.
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.