According to Boyle's law for a perfect gas
1
\(\frac{{{T_2}}}{{{T_1}}}\; = \;\frac{{{P_2}}}{{{P_1}}}\) if V is kept constant
2
\(\frac{{{T_2}}}{{{T_1}}}\; = \;\frac{{{V_2}}}{{{V_1}}}\) if P is kept constant
3
\(\frac{{{P_1}}}{{{P_2}}}\; = \;\frac{{{V_2}}}{{{V_1}}}\) if T is kept constant
4
None of these