Answer
a) Yes
b) No
Work Step by Step
a) A Giffen good is a good for which an increase in the price increases the quantity demanded. Goods that are Giffen goods violate the law of demand (that an increase in price will decrease quantity demanded). Thus, Giffen goods are inferior goods.
b) Not all inferior goods are Giffen goods. If the income effect of the good is less than the substitution effect of the good, then there would be a normal demand curve for the good.