At the top of the mountain, the thermometer reads `0^(@)C` and the barometer reads `710 mm Hg`. At the bottom of the mountain the temperature is `30^(@)C` and the pressure is `760 mm Hg`. The ratio of the density of air at the top with that at the bottom is

Explanation

`rho=(PM)/(RT)`
Hence `(rho_(1))/(rho_(2))=(P_(1))/(P_(2))xx(T_(2))/(P_(2))`
`therefore(760mm)/(303K)xx(273K)/(710mm)=(0.964)/(1)`
`thereforerho_(1):rho_(2)=0.964:1`