Find the value of c for which the line 3x + cy = 5
(a) Passes through the point (3, 1);
(b) Is parallel to the y-axis;
(c) is parallel to the line 2x + y = -1;
(d) Has equal x- and y-intercepts;
(e) Is perpendicular to the line y - 2 = 3(x + 3).