Answer
a. Decreased Entropy
b. Increased Entropy
c. Increased Entropy
d. Remained the Same
Work Step by Step
a. The equation gets balanced making the reaction orderly.
b. Urea is solid in physiological state and once hydrolyzed, it releases gas.
c. The solution of $0.5m$ of NaCl has higher entropy as the bar between the two sides does not separate the molecules of Na and Cl. There are more ways to be disordered.
d. No energy was released in the conversion of 3-Phosphoglycerate to 2-Phosphoglycerate.