Convergence of z_n: A Complex Series Question with Alpha Boundaries

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z_n=\rho_ne^{i\theta_n}\\ is a series of complex numbers which differs 0 for which

-\alpha<=\theta_n<=\alpha\\



A.does \sum z_n\\ converge



B.does \sum |z_n|\\ converge
 
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What have you tried? Do you know any theorems for determining whether an infinite series converges?
 
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