Calculate $\Delta U$ if $2 \ kJ$ heat is released and $10 \ kJ$ of work is done on the system. (in $kJ$)

Based on the first law of thermodynamics,which one of the following is correct?

Calculate the change in internal energy of the system if $25 \ kJ$ of work is done by the system and it absorbs $10 \ kJ$ of heat. (in $kJ$)

An isolated chamber is divided into two halves by a partition,with an ideal gas in one half. By making a hole in the partition,the gas is allowed to expand to the full chamber. Among the following,the parameter which changes in the process is

For the reaction,$N_{2(g)} + 3 H_{2(g)} \rightarrow 2 NH_{3(g)}$,$\Delta H$ is equal to

$A$ system does $200 \, J$ of work and at the same time absorbs $150 \, J$ of heat. The magnitude of the change in internal energy is $..... \, J.$ (Nearest integer)