Physics - Heat & Thermo Question with Solution | TestHub

A straight line through the origin from $L$ to $M$, then a vertical line downward from $M$ to $N$

A straight line through the origin from $L$ to $M$, then a horizontal line from $M$ to $N$

A horizontal line from $L$ to $M$, then a vertical line from $M$ to $N$

A curve from $L$ to $M$, then a line through the origin from $M$ to $N$