Which of the following statements is correct regarding a step-down transformer?

$A$ small town with a demand of $800 \; kW$ of electric power at $220 \; V$ is situated $15 \; km$ away from an electric plant generating power at $440 \; V$. The resistance of the two-wire line carrying power is $0.5 \; \Omega/km$. The town gets power from the line through a $4000-220 \; V$ step-down transformer at a sub-station in the town.
$(a)$ Estimate the line power loss in the form of heat.
$(b)$ How much power must the plant supply,assuming there is negligible power loss due to leakage?
$(c)$ Characterise the step-up transformer at the plant.

The primary winding of a transformer has $500$ turns,whereas its secondary has $5000$ turns. The primary is connected to an $ac$ supply of $20\, V$,$50\, Hz$. The secondary will have an output of

$A$ transformer operating at primary voltage $8\,kV$ and secondary voltage $160\,V$ serves a load of $80\,kW$. Assuming the transformer to be ideal with a purely resistive load and working on unity power factor,the resistances in the primary and secondary circuits would be:

Which device is used to transmit voltage over large distances and why?

Explain the use of a transformer for the distribution of power over long distances.