I need help with astonomy questions there.....?

explain why the north pole is always in sunlight during summer in the northern hemusphere. 2.during a new phase of the moon , we can't see it because no sunlight reaches the side facing earth. yet sometime when there is a thin crescent visible, we do see a faint image of the rest of the moon. explain what might cause this happen. 3.where have large amount of water been detected on the moon?4.earth is closest to the sun during which season in the northern and southern hemisphere?