You have two pieces of wire that allow electrons to pass through them when they are connected to each other. if you insert a metal cable between the wires, electrons still flow easily the metal cable is ?
a. a circuit
b. an insulator
c. a fuse
d. a conductor

Suppose that three astronomical objects, 1, 2, and 3 are observed to lie on a line, and the distance from object 1 to object 3 is d. object 1 has four times the mass of object 3, and seven times the mass of object 2. find the distance between objects 1 and 2 for which the net force on object 2 is zero.