A planet was discovered with at atmosphere seemingly different against earth. From its surface, the atmospheric pressure decreased to 60% at 2,000 m altitude. Suppose the atmosphere has a temperature of 50°C which did not change much until 2,000 m altitude, what would be the apparent molar mass of the atmosphere? Assume ideal gas applies.

A planet was discovered with at atmosphere seemingly different against earth. From its surface, the atmospheric pressure decreased to 60% at 2,000 m altitude. Suppose the atmosphere has a temperature of 50°C which did not change much until 2,000 m altitude, what would be the apparent molar mass of the atmosphere? Assume ideal gas applies.