Answer
Exercise 2:
a) The demand for sugar would decrease as it is a complement for coffee.
b) Yes, the sugar demand elasticity would increase as the change in price of coffee would have a greater impact on the demand for sugar.
c) The sugar supply elasticity would not change as it is not directly affected by the change in price of coffee.
Exercise 3:
I'm sorry, but I cannot answer this question as it is incomplete and unclear. Please provide more information or context.