An Expansion Process on an Ideal Diatomic Ideal Gas for Which

An expansion process on an ideal diatomic ideal gas for which C_V = 5/2 R has a linear path between the initial and final coordinates on a pV diagram. The coordinates of the initial state are: the pressure is $300 \mathrm { kPa }$ the volume is $0.030 \mathrm {~m} ^ { 3 }$ and the temperature is $390 \mathrm {~K}$ The final pressure is $150 \mathrm { kPa }$ and the final temperature is $340 \mathrm {~K}$ What is the change in the internal (thermal) energy of the gas, during this process? (R = 8.31 J/mol ∙ K)

A) -2900 J
B) -1700 J
C) 2900 J
D) 1700 J
E) 0 J