Let $$\mathrm {P}$$ be the product of the roots of $$z^6+z^4+z^3+z^2+1=0$$ that have a positive imaginary part, and suppose that $$\mathrm {P}=r(\cos{\theta^{\circ}}+i\sin{\theta^{\circ}})$$, where $$0 < r$$ and $$0\leq \theta < 360$$. Find $$\theta$$.

(第十四届AIME1996 第11题)