The volume of one mole of the gas is changed from $V$ to $2V$ at constant pressure $p$. If $\gamma$ is the ratio of specific heats of the gas,what is the change in internal energy of the gas?

Assertion : Heat and work are modes of energy transfer to a system resulting in change in its internal energy.
Reason : Heat and work in thermodynamics are state variables.
The correct option among the following is

In a thermodynamics process,the pressure of a fixed mass of a gas is changed in such a manner that the gas releases $20 \ J$ of heat and $8 \ J$ of work is done on the gas. If the initial internal energy of the gas was $30 \ J$,what will be the final internal energy in $J$?

In how many ways can the internal energy of a system be changed?

In changing the state of a thermodynamic system from state $A$ to state $B$, the heat supplied to the system is $Q$ and the work done by the system is $W$. The change in its internal energy is

During a thermodynamic process,the pressure of a fixed mass of gas is changed in such a way that the gas releases $20 \ J$ of heat and $10 \ J$ of work is done on the gas. If the initial internal energy of the gas is $40 \ J$,then the final internal energy is ...... $J$.