Indicate which of the following activities are part of mid-level design (M), low-level (L), or Programming (P).

(a) Choosing a sorting algorithm.

(b) Deciding whether a class should be a sub-class of another class.

(c) Naming the local variables in a method.

(d) Deciding how to implement an enumeration type.

(e) Deciding which interfaces a class should implement.

(f) Figuring out how two threads should synchronize when using the same object.

(g) Breaking a large class into several collaborating classes.