7. [15] Tipler & Mosca (6\" edition) Chapter 22, problem 44 A sphere of radius R has volume charge density p = Or2 for r R. (a) Find the total charge on the sphere. (b) Find the expressions for the electric eld inside and outside the charge distribution (c) Using MATLAB or other programs, sketch the magnitude of the electric eld as a function of the unitless parameter #12, where r is the distance om the sphere's center. Is the electric eld continuous at r = R? 8. [15] Hpier & Mosca (6th edition) Chapter 23, problem 54 A disk of radius R has a surface charge distribution given by 0'= O'oR/r where on is a constant and r is the distance from the center of the disk. (0) Find the total charge on the disk. (b) Find an expression for the electric potential at a distance x from the center of the disk on the axis that passes through the disk's center and is perpendicular to its plane