Calculate the change in entropy of air using both the ideal-gas table and the entropy departure chart

Question:

Calculate the change in entropy of air using both the ideal-gas table and the entropy departure chart if its state changes from:
a) 520° R and 180 psia to 1600° R and 1000 psia
b) 600°R and 250 psia to 1800°R and 3000 psia
c) 400° R and 100 psia to 440° R and 4000 psia