In a balanced three$-$phase system, the source has an abc sequence, is Y $-$connected, and $V_{st}=\frac{210}{{?}_{-}}30V.$ The source feeds two loads, both of which are Y$-$connected The impedance of load $1$ is $25+j30\frac{}{}.$ The complex power for the a$-$phase of load $2$ is $\frac{900}{{?}_{30}}VA.$

Part A

Find the total complex power supplied by the source.