According to the first law of thermodynamics, heat given to a system is equal to the work done by the gas plus change in internal energy. Therefore,

$∆Q=∆U+W$

Work done for isobaric process is given by, 

$$\begin{gathered} W=nR∆T \\ \Rightarrow nR∆T=200 \mathrm{J} \end{gathered}$$

Heat given in isobaric process will be,

$$\begin{gathered} ∆Q=n{C}_P∆T=\frac{7}{2}nRT \\ \Rightarrow ∆Q=700 \mathrm{J} \end{gathered}$$