Which of the following is not equal to zero in a cyclic process?

What is the change in internal energy if a system gains $x \ J$ of heat and $y \ J$ of work is done on it?

Calculate the change in internal energy $(\Delta U)$ if an ideal gas expands from $0.5 \text{ dm}^3$ to $3.5 \text{ dm}^3$ at a constant pressure of $2 \text{ bar}$ by absorbing $1800 \text{ J}$ of heat energy. (in $\text{ J}$)

For the reaction $N_2(g) + 3H_2(g) \rightarrow 2NH_3(g)$ at constant temperature and pressure,if $\Delta H$ and $\Delta U$ are the enthalpy and internal energy changes for the reaction,which of the following equations is correct?

$A$ gas present in a cylinder expands against a constant pressure of $1 \, atm$ from a volume of $2 \, L$ to a volume of $6 \, L$. In doing so,it absorbs $800 \, J$ of heat from the surroundings. The change in internal energy of the process is ..... $J$.

Which of the following set of properties is correct when one mole of a gas is heated keeping volume constant by increasing temperature and supplying $500 \ J$ of heat?