As per Kepler's first law we know that all planets and all satellites revolves in elliptical path with one of its focii as Sun or planet around which satellite and planets are revolving.
Now here we need to know about the focii of moon which is revolving around Earth in its elliptical path.
So as per same law we can say that since moon is revolving around the Earth so its focii must be Earth
The question is oversimplified, and pretty sloppy.
Relative to the Earth . . . The Moon is in an elliptical orbit around us, with a period of 27.32... days, and with the Earth at one focus of the ellipse.
Relative to the Sun . . . The Moon is in an elliptical orbit around the Sun, with a period of 365.24... days, and with the Sun at one focus of the ellipse, and the Moon itself makes little dimples or squiggles in its orbit on account of the gravitational influence of the nearby Earth.
I'm sorry if that seems complicated. You know that motion is always relative to something, and the solar system is not simple.
<span>A lubricant such as oil, grease, graphite powder can reduce the friction between two surfaces. Or using metal balls to space them and reduce the contact surface area as used in ball bearings.</span>
Buhrs atomic model differed from ruthofords because it explained that electrons exist in specified energy levels surrounding the nucleus. This means that, Ruthoford believed that electrons can't do very much. However, Buhrs' model showed that electrons are much more powerful than anyone else believes they can be.