Conditional Variance of a Random Variable?

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Say I have the following random variable:

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Where $\varphi_{i}$ and $\rho_{j}$ are themselves independent random variables (note: given particular values for $\varphi_{i}$ and $\rho_{j}$, $Q_{ij}$ is a Bernoulli random variable with parameter $\varphi_{i}\rho_{j}$). Find,

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Here is what I have (I used the law of total variance):

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Is my reasoning correct? For some reason I am not confident in it?