Which law of thermodynamics can be considered as the definition of temperature?

The relation between change in internal energy $(\Delta E)$,change in enthalpy $(\Delta H)$,and work done $(W)$ is represented as:

Which one of the following is an extensive property?

Calculate the work done in joule if $2 \ mol$ of an ideal gas expands isothermally from $15.5 \ dm^3$ to $20 \ dm^3$ at a constant external pressure of $1 \ atm$. (in $J$)

What are extensive properties?

$2 \ \text{moles}$ of a gas undergoes a change in state from $(2 \ \text{bar}, 40 \ \text{L})$ to $(5 \ \text{bar}, 15 \ \text{L})$ at a constant temperature. If the change in internal energy is given by $35 \ \text{bar-L}$, then the enthalpy change for the process will be: (in $\text{bar-L}$)