A gas has second virial coefficient $B=-80\mathrm{mL}\mathrm{mo}{\mathrm{l}}^{-1}$ at $300\mathrm{K}$ ($R=0.0821\mathrm{L}\mathrm{atm}{\mathrm{K}}^{-1}\mathrm{mo}{\mathrm{l}}^{-1}$). Neglecting higher terms, which statements are correct?

1. AAt $5.0\mathrm{atm}$ the compressibility factor is about $0.984$
2. BThe pressure at which $Z=0.950$ is about $15.4\mathrm{atm}$
3. CIf the gas obeyed $B=b-a/RT$ with $b=0.040\mathrm{L}\mathrm{mo}{\mathrm{l}}^{-1}$, then $a$ would be about $2.96{\mathrm{L}}^2\mathrm{atm}\mathrm{mo}{\mathrm{l}}^{-2}$
4. DThe gas is above its Boyle temperature