A diatomic gas at pressureP1= 6.0 × 105-Pa undergoes an isobaric expansion from a volume ofV1= 0.99-m3to a volumeV2= 1.9-m3, then undergoes an isovolumetric change to pressureP2= 1.1 × 105-Pa, followed by an isobaric contraction back toV1and finally an isovolumetric change in pressure toP1. How much work does the gas do?