Please correct and provide explanation

(11.) A conducting sphere has been given an overall positive charge of +20 nC. Surrounding the sphere is a hollowed out cube which is also a conductor. The cube has been given an overall charge of -5nC. In all questions, any accompanying explanations will be used to offset poor drawing skills. (a.) Draw pluses on the sphere showing where that positive charge is located. (Neutral regions should be left blank.) Assume that the charge will be uniformly distributed. (5pts) (b.) Draw pluses and minuses on the cube to show the regions of charge. (Neutral regions should be left blank.) Hint: This should require a simple calculation. (5pts) (c.) Sketch the electric field lines for this situation. The exact shape and number of lines will not be graded, but their direction should be clearly labeled with arrowheads and some indication of the angle should be shown. (10pts) E= O no field lines in conductors . charge only on suface . To make F -O - Inc must be inside surface - aditional - Inc left over must be outtive surface . field lines at 90 to surface . field lines frominf to neg charge and from pos toreg +12