Answer:
![V_2 = 606.9 m^3](https://img.qammunity.org/2020/formulas/physics/high-school/eba742y25nri4vp2er5ygjtf55clzownaj.png)
Step-by-step explanation:
By ideal gas equation law we know that
PV = nRT
now we know that when balloon rises to certain level then the number of moles will remains same
so we can say
![n_1 = n_2](https://img.qammunity.org/2020/formulas/physics/high-school/gjha9lwpwfpmpegvi7pjtfl9lmde304wod.png)
![(P_1V_1)/(RT_1) = (P_2V_2)/(RT_2)](https://img.qammunity.org/2020/formulas/physics/high-school/d64aam8nxx10wy1huqamslemihzbm631dc.png)
now plug in all data to find the final volume of the balloon
![(754* 219)/(R(298)) = (210 * V_2)/(R(230))](https://img.qammunity.org/2020/formulas/physics/high-school/fg2ft3gf9ls8g4ps2he6rq1z4tpihzm3qa.png)
![V_2 = (230* 754 * 219)/(210 * 298)](https://img.qammunity.org/2020/formulas/physics/high-school/qdtfotx9o7el8n3ccv3ifi6aym73gwzo54.png)
![V_2 = 606.9 m^3](https://img.qammunity.org/2020/formulas/physics/high-school/eba742y25nri4vp2er5ygjtf55clzownaj.png)