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A cut in train fares leaves the total revenue from train fares the same as before. This is an example of (a) Perfectly elastic demand. (b) Elastic demand. (c) Unitary elasticity of demand (d) Inelastic demand. Which one of the following statements is correct? (a) Cardinal utility involves the idea that utility can be measured in some way. (b) Both cardinal and ordinal utility involves the ranking of different bundles of consumer goods in order of preference. (c) Total utility decreases as long as marginal utility is positive. (d) None of the options are correct. The threshold value for the cross elasticity of demand that determines whether a product is a substitute or a complement is: (a) 1: (b) (c) -1; (d) Infinity. The demand for cooldrink is price elastic if: (a) An increase in price results in an increase in total revenue. (b) A decrease in price results in an increase in total revenue. (c) The good is a necessity. (d) A decrease in price results in a decrease in total revenue