Suppose the class Sandwich implements the Edible interface, and you are given the variable declarations

Sandwich sub = new Sandwich();
Rectangle cerealBox = new Rectangle(5, 10, 20, 30);
Edible e = null;

Which of the following assignment statements are legal?
a. e = sub;
b. sub = e;
c. sub = (Sandwich) e;
d. sub = (Sandwich) cerealBox;
e. e = cerealBox;
f. e = (Edible) cerealBox;
g. e = (Rectangle) cerealBox;
h. e = (Rectangle) null;