Which of the process described below are irrevesible?

Options

A. The increase in temperature of an iron rod by hammering it
B. A gas in a small container at a temperature `T_1` is brought in contact with a big reservoir at a higher Temperature. `T_2` which inverses the temperature of the gas
C. A quasi - state isothermal expansion of an ideal gas in cylinder fitted with a frictionless piston
D. An ideal gas is enclosed in a piston cylinder arrangement with adiabatic Walls. A weight W is added to the piston, resulting in compression of a gas

Answer

A, B, D