4. Sketch the cross sections for the equation f (a), y, z) = c. (a) f(:1:,y,z) = 11:2 + y2 22; c = 0; Cross sections: 33 = 1,0, 1, 2 (b) f($,y, z) = 23:2 + y2 + 3Z2; c = 4; Cross sections: x = 1,0, 1, 2 5. Convert the point (x,y,z) = (1, 1,\\/) into cylindrical coordinates (730,2) and spherical coordinates (p, (15, 0)