1.  q0

2.  q2, q4, q6, q7

3.  Each state has exactly two outgoing transitions: one for 0 and one
    for 1.  This *is* required for deterministic FSMs like the ones
    you will write for PS 10.

4.  q3. You won't always need a "black hole" state, but it's useful when:

      - the condition that you're using the FSM to test for can
        become unreachable (e.g., you're testing for strings with at most
        two 1s, and you have already seen three 1s)

      - once you attain the condition that you're testing for, any
        additional characters won't change that condition (e.g., you're
        testing for strings with at least two 1s, and you have already
        seen two 1s)

5.  accepted: 10, 010, 101010
    not accepted: 0, 111, 0100

6.  This FSM accepts bit strings that are at least two bits long and 
    that have alternating bits (i.e., bits that alternate between 0 and 1 
    or between 1 and 0).

7.  Yes. See the separate file for one possible simplified version.