Which of the following is an intensive property?

For $1 \, \text{mole}$ of an ideal gas,isothermal expansion occurs from a volume of $2 \, L$ to $6 \, L$ at a temperature of $300 \, K$. The value of $\Delta U$ for this process is .............

Which of the following is correct regarding the internal energy of a substance?

Calculate work done if $1 \ mole$ of an ideal gas expands isothermally from $2 \ dm^3$ to $2.8 \ dm^3$ against constant external pressure $1 \ atm$. (in $J$)

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

Fill in the blanks:
$(i)$ The process of attaining thermal equilibrium between any two heat-conducting bodies is called the $\dots\dots$ law of thermodynamics.
$(ii)$ The law of thermodynamics is actually the law of $\dots\dots$.
$(iii)$ $A$ thermometer measures temperature according to the $\dots\dots$ law of thermodynamics.