Spaceship entering mars!! okay guys so you have to open this file to read the question accuretely.. i have done some calculations but not sure if they are correct. So just this as best as i can, fist i figure out my semi-minor axis = a by 150km +150 KM +230 km =530km (major axis) now to get me semi minor axis i will just divide it by 2 . Giving me 265km! Focal lenght= 265km - earths disntace to the sun (150 km) =115 km Now to get my semi minor axis i use the equation b2=(a2-f2) (530Km-300km)=b2 b=150km