Which of the following is correct?

For a reaction at $25^o C$,$\Delta H > 0$ and $\Delta S > 0$. Under what conditions will this reaction become spontaneous?

An ideal gas expands from an initial volume of $5 \text{ dm}^3$ to $15 \text{ dm}^3$ against a constant external pressure of $2 \text{ atm}$. What is the work done by the gas (in $\text{ J}$)?

For the reaction $CaCO_{3(s)} \to CaO_{(s)} + CO_{2(g)}$,given $\Delta H^o = 178.3 \, kJ$ and $\Delta S^o = 160 \, J \cdot K^{-1}$. At what temperature will the reaction become spontaneous?

For the change $H_2O_{(l)} \to H_2O_{(g)}$ at $P = 1 \ atm$ and $T = 373 \ K$,the free energy change $\Delta G = 0$. This indicates that:

$A$ $4.50 \ g$ sample of methane occupies $12.7 \ L$ at $310 \ K$. Calculate the work done in $J$ when the gas undergoes isothermal expansion against a constant external pressure of $200 \ torr$ until the volume increases by $3.3 \ L$. (in $.99$)