2. The CSUN IEEE chapter is to choose a president, treasurer and secretary, all different, from a group of 10 students. How many different choices of officers are possible if: a. There are no restrictions b. A and B will not serve together c. C and D will serve together or not at all d. E must be an officer e. F will serve only if he is a president. Solution a.There are no restrictions- 10C3 e. F will serve only if he is a president.-10C1.