• The tutorial (T1, T2, or T3) in which you are registered.
Question 2: Answer each of the following 7 questions; for each of them, give a short justification. How many strings of eight letters (from A, B, C, . . . , Z) are there
1. if letters can be repeated?
2. if no letter can be repeated?
3. that start with PQ (in this order), if letters can be repeated?
4. that start with PQ (in this order), if no letter can be repeated?
5. that start and end with PQ (in this order), if letters can be repeated?
6. that start with XYZ (in this order) and end with QP (in this order), if letters can be repeated?
7. that start with XYZ (in this order) or end with QP (in this order), if letters can be repeated?
Question 3: How many bitstrings of length 8 are there that contain 4 (or more) consecutive 0’s or contain 4 (or more) consecutive 1’s? Justify your answer.
It is sufficient to give the answer in terms of binomial coefficients (but you have to justify your answer).
Question 5: Determine how many different strings can be obtained by reordering the letters of the word MississippiMills. (This is a town close to Ottawa.)
