Which of the following is $NOT$ a state function?

An ideal gas is allowed to expand from $2 \ dm^3$ to $6 \times 10^{-3} \ m^3$ against a constant external pressure of $1 \ bar$. The work done in $kJ$ is (in $kJ$)

When an ideal gas expands isothermally from $5 \ m^3$ to $10 \ m^3$ at $25 \ ^{\circ}C$ against a constant pressure of $10^7 \ N \cdot m^{-2}$,then the work done on the gas is (in $MJ$)

Given below are two statements $ : $
Statement $I :$ When a system containing ice in equilibrium with water $(\text{liquid})$ is heated, heat is absorbed by the system and there is no change in the temperature of the system until whole ice gets melted.
Statement $II :$ At the melting point of ice, there is absorption of heat in order to overcome intermolecular forces of attraction within the molecules of water in ice, and the kinetic energy of molecules is not increased at the melting point.
In the light of the above statements, choose the correct answer from the options given below $ : $

The species which by definition has $ZERO$ standard molar enthalpy of formation at $298 \ K$ is

An ideal gas is allowed to expand against a constant pressure of $2 \ bar$ from $10 \ L$ to $50 \ L$ in one step. Calculate the amount of work done by the gas. If the same expansion were carried out reversibly,will the work done be higher or lower than the earlier case? (Given that $1 \ L \ bar = 100 \ J$)