By the looks of it, about $58.
Depends on whose signature it is
A genuine signature of JFK is worth about 2.500$
$300000
Assuming you have a LEGITIMATE certificate of authenticity and depending on how old the stick is it should be worth around $75-$100 if it is in near mint condition and the signature is not faded.
15
250$
nothing.
Nothing
100000000000000000
$29,450
0.01
304,000