Let F be defined as in the previous question. Consider the closed curve ( on a unit sphere, as shown in pink in the sketch below, traversed in the direction indicated by the arrows. Which of the following statements about J F . dr is true? Itis 0 O We can't evaluate this unless we know the exact shape of the curve O Green's theorem applies in this case O We can't evaluate this unless we know the choice of normal to the surface O It is strictly negative It is strictly positive