Why do we consider two specific heats heat for a gas?

Why do we consider two specific heats of a gas? OR Why specific heat at constant pressure is greater than specific heat at constant volume?

Specific heat of water is

The specific heat of ice at 0^@C is

Define Molar specific heat capacities of gases.

The difference between the two molar specific heats of a gas is 8000 J kg^-1 K^-1 . If the ratio of the two specific heats is 1.65. Calculate the two molar specific heats.

The ratio of specific heats (y) for monoatomic gas is.......

Why do we see moonlight ?

Which principle is used to measure the specific heat capacity of a substance?