In Section 3.7 we described line codes for pulse-code modulation

In Section 3.7 we described line codes for pulse-code modulation. Referring to the material presented therein, formulate the signal constellations for the following line codes:
(a) Unipolar nonreturn-to-zero code
(b) Polar nonreturn-to-zero code
(c) Unipolar return-to-zero code
(d) Manchester code