When the Price of a Bicycle Falls from $220 to $180

question 25

Multiple Choice

When the price of a bicycle falls from $220 to $180 and other things remain the same, I. the quantity of bicycles demanded increases from 150 to 250 an hour.
II. the quantity of skateboards demanded decreases from 125 to 75 an hour.
III. the quantity of bicycle helmets demanded increases from 170 to 230 an hour.
Bicycle helmets and bicycles are ________ because a fall in the price of a bicycle brings ________ in the quantity demanded of bicycle helmets. The cross elasticity of demand for bicycle helmets with respect to bicycles is ________.

• A)complements; an increase; -1.5
• B)substitutes; a decrease; 1.5
• C)substitutes; an increase; -0.67
• D)complements; a decrease; 0.67
• E)complements; an increase; 1.5

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Definitions:

Radioactively Labeled

A technique used in research that involves attaching radioactive isotopes to molecules or cells to trace biochemical processes or track the spread of substances in an organism.

Citric Acid

An organic acid that is a crucial intermediate in the citric acid cycle, involved in the metabolism of energy in living organisms, and widely used as a preservative and flavoring in the food industry.

Pyruvate

A key end-product of glycolysis, which is converted into acetyl CoA that enters the Krebs cycle when oxygen is present.

Mitochondrial Matrix

The material within the inner membrane of a mitochondrion that contains enzymes, mitochondrial DNA, and ribosomes for protein synthesis.