Ineed to get my school work done so i can pass it's a complicated story, it's just science plase!

If anyone who can me with this hw? i would really appreciate it

Two identical stars with mass m orbit around their center of mass. each orbit is circular and has radius r, so that the two stars are always on opposite sides of the circle. (a) find the gravitational force of one star on the other. (b) find the orbital speed of each star and the period of the orbit. (c) how much energy would be required to separate the two stars to infinity?

Describe how the motion of a spring being pushed forward and backward is similar to the motion of air particles in a sound wave.