Technician a says when removing camshaft belts or chains always follow the manufacturer’s directions regarding the potential use of cam holding tools. technician b says not using cam holding tools during belt or chain removal can damage camshaft bearings. who is correct?

Let r be a robotic arm with a fixed base and seven links. the last joint of r is a prismatic joint, the other ones are revolute joints. give a set of parameters that determines a placement of r. what is the dimension of the configuration space resulting from your choice of parameters?