Question

Determine two coterminal angles (positive and negative a) 0=240

Answer 1

\[\theta=240 degrees\]

Answer 2

Coterminal angles are angled measured in the standard position (i.e. from the positive x-axis to the terminal arm) which land on the same terminal side:
http://www.mathwords.com/c/coterminal.htm

So, all you have to do is add multiples of 360 degrees to your original angle. You need one that's positive and one that's negative, so:

\[240^{o}+360^{o}=600^{o}\]and\[240^{o}-360^{o}=-120^{o}\]are two such angles.