Yes.
In (a),if R chooses to take an awarded fair catch, the ball would be placed on the R25 yard line.
The 25 yard line is the spot of Kick catching interference (the R 10) plus 15 yards.
Note that R can now put the ball in play via a snap or a free kick
Good catch sczeebra, The Case Book has not caught up with the Rules Book as is often the case with any Rule change
I will forward this on to the Editorial Committee and we shall see if this can still be corrected in time for the 2016 Case Book
Again, good catch sczeebra!