Which among the following is $TRUE$ for an isobaric process?

Express the change in internal energy of a system when
$(i)$ No heat is absorbed by the system from the surroundings,but work $(w)$ is done on the system. What type of wall does the system have?
$(ii)$ No work is done on the system,but $q$ amount of heat is taken out from the system and given to the surroundings. What type of wall does the system have?
$(iii)$ $w$ amount of work is done by the system and $q$ amount of heat is supplied to the system. What type of system would it be?

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

$A$ heat engine absorbs heat $Q_1$ at temperature $T_1$ and heat $Q_2$ at temperature $T_2$. Work done by the engine is $(Q_1 + Q_2)$. This data

What is the change in internal energy of the system when the work done by the system is $150 \ J$ and the system releases $300 \ J$ of heat?

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 $kJ$)