EDIT: Sorry, looks like someone beat me to it, and posted the correct solution - mine is slightly off - IGNORE!
For the last question, I worked out the two centers (-1,1) and (2,-3), then I did distance formula which worked out to be 5. Then so they don't intersect, the radius of C2 would have to be less than 6 (since 11-5=6). I then substituted this into the formula r<square root of (g^2+f^2-c), which worked out that 6<square root of (13-p). Therefore p must be less than 14 (can't square root a negative).
so therefore, 36<13-p
23>-p
p>-23
-23<p<14
I'm fairly confident that's how it is done, but if not then correct me please! Can't go into advanced higher with faulty higher maths! :P lol