$2.$ You are given the $3$ phase transmission line below. Assume the line is transposed. Do the following.

Line $1$

Length $\backslash (=90\backslash )$ miles

Height at tower $\backslash (=77\backslash$mathrm$\{$ft$\}\backslash )$

Heigth at midspan $\backslash (=33\backslash$mathrm$\{$ft$\}\backslash )$

Horizontal spacing between adjacent phases $\backslash (=35\backslash$mathrm$\{$ft$\}\backslash )$

Number of conductors per bundle $\backslash (=4\backslash ),$ positioned as shown in figure

Bundle spacing $\backslash (=18\backslash )$ inches

Conductor outside diameter $\backslash (=1\mathrm{.}0\backslash )$ in

AC Resistance $\backslash (=0\mathrm{.}145\backslash$mathrm$\{$ohm$\}/\backslash$mathrm$\{$mile$\}\backslash )$

Conductor GMR $\backslash (=0\mathrm{.}4260\backslash )$ in

$($a$)$ Calculate the positive sequence series impedance per unit length

$($b$)$ Calculate the positive sequence shunt admittance per unit length

$($c$)$ Calculate line model parameters for the appropriate $($short$,$ medium, or long line$)$ model. Explain your choice.

$($d$)$ If one end of the line is open circuited, and the other end is connected to a $500$ kV ideal source calculate $(1)$ the RMS phase current entering the line and $(2)$ the line to neutral voltage at the open circuited end of the line.

$($e$)$ How does the use of bundled conductors impact the line parameters $(\backslash (\backslash$mathrm$\{$R$\},\backslash$mathrm$\{$L$\}\backslash ),$ and C $)?$ What are the advantages and disadvantages of using bundled conductors?