Answer
The final stable decay products are:
$e^+ + \nu + \bar{\nu} + \nu + e^- + \nu + \bar{\nu} + \bar{\nu} + e^+ + \nu + \bar{\nu}+ \nu$
Work Step by Step
$A_2^+ \rightarrow \rho^0+\pi^+$
$A_2^+ \rightarrow \pi^+ + \pi^- +\pi^+$
$A_2^+ \rightarrow \mu^+ + \nu + \mu^- + \bar{\nu} + \mu^+ + \nu$
$A_2^+ \rightarrow e^+ + \nu + \bar{\nu} + \nu + e^- + \nu + \bar{\nu} + \bar{\nu} + e^+ + \nu + \bar{\nu}+ \nu$
The final stable decay products are:
$e^+ + \nu + \bar{\nu} + \nu + e^- + \nu + \bar{\nu} + \bar{\nu} + e^+ + \nu + \bar{\nu}+ \nu$
