One mole of tungsten (6 × 1023 atoms) has a mass of 184 grams, and its density is 19.3 grams per cubic centimeter, so the center-to-center distance between atoms is 2.51 × 10-10 m. You have a long thin bar of tungsten, 2.6 m long, with a square cross section, 0.07 cm on a side. You hang the rod vertically and attach a 98 kg mass to the bottom, and you observe that the bar becomes 1.42 cm longer. From these measurements, it is possible to determine the stiffness of one interatomic bond in tungsten. 1) What is the spring stiffness of the entire wire, considered as a single macroscopic (large scale), very stiff spring?