(e) Determine 1-one reveals a robotic arm that may be built up of two sections Arm1 and Arm2 . Arm1 can rotate all around the shoulder joint A, even though Arm2 is connected to Arm1 at the elbow joint B, and can rotate around the joint B. 完美细心的售后：我们的专业作家团队从事写作已经有非常长的时间，但是难免会遇到一些不完美的地方，您可以反馈给客服团队，无条件直到修改至满意为止！ 英国... http://summary63973.blogdigy.com/everything-about-summary-24860253