$3)$ Convert the microgrid system to a per$-$unit representation using a base of $1$ MVA. Calculate the per$-$unit values for the transformer, solar PV array, BESS, and building loads.

$4)$ Assuming balanced three$-$phase loads, calculate the line currents and phase voltages at each building's service entrance when operating at full load. Express your answers in both per$-$unit and actual values.

$5)$ Develop a single$-$line diagram of the microgrid, treating each building as a load bus, the transformer as the slack bus, and the solar PV$/$BESS as one generation bus.

$6)$ Construct the Y$-$bus matrix for the microgrid. The transformer is connected to load bus$\backslash$#$1,$ bus$\backslash$#$1$ is connected to $\backslash$#$2,$ and $\backslash$#$2$ is connected to load bus$\backslash$#$3$ through lines with the impedance of j$0\mathrm{.}1$X per$-$unit where $\backslash ($ X $\backslash )$ is the last digit of your ULID. Also, the BESS$/$PV bus $($generation bus$)$ is connected to load bus $\backslash (\backslash$# $3\backslash )$ with the impedance of j $0\mathrm{.}2$ X $.$ So$,$ we're going to have $4$ lines in our single line diagram.

$7)$ Write power flow equations $($you don't need to solve them$)$