1.Over the course of the year,the sun follows a path around

1.Over the course of the year,the sun follows a path around the sky called the ecliptic,which corresponds to the plane of the solar system (where all the planets orbit).At what times of year does the Sun cross the celestial equator?
2.Start the animation.Under "Star Controls:star patterns..." add the Big Dipper constellation.Note you can change the observer's location by dragging the crosshairs across the lower left map.Where on Earth is it impossible (at any time) to see the Big Dipper?
3.What are degrees,arcminutes,and arcseconds used for?What are the relationships among these units of measure?