Answer:
(1) Relative prices; Utility
(2) Purchasing power; Relative prices
Step-by-step explanation:
Substitution effect:
When there is a change in the quantity demanded for a good due to any change in the price level of the good is known as substitution effect. If the price of a good decreases then as a result there is a change in the consumption for all the goods due to change in the relative prices and holding the utility constant.
Income effect:
When there is a change in the quantity demanded for a good due to change in the purchasing power of the consumer because of any change in the price level and we are holding relative prices constant.