What is the expression 1 in. = 2.54 cm properly called?

Correct Answer: D

Rationale: The correct answer is D: Exact Equivalent. The expression 1 inch = 2.54 cm is a direct and precise conversion between inches and centimeters, making it an exact equivalent. It is not related to the Law of Conservation of Units (A) as this principle pertains to the conservation of physical quantities in a system. The International Yard (B) is a unit of measurement, but it is not the term for the given expression. Similarly, while the conversion factor in the expression is standard, it is specifically an exact equivalent and not just a general standard conversion factor (C). Therefore, D is the most appropriate term to describe this specific conversion relationship.

Correct Answer: A

Rationale: In the metric system, 'km' stands for kilometer, which is a unit of length equal to 1,000 meters. This choice is correct as 'kilometer' is the standard unit for measuring long distances. Choice B, 'kilomole,' is incorrect as it is a unit in chemistry representing a quantity of substance. Choice C, 'kilobyte,' is incorrect as it is a unit of digital information storage, not a unit of measurement. Choice D, 'knot,' is incorrect as it is a unit of speed used in navigation and aeronautics, not a unit of length in the metric system.

Correct Answer: A

Rationale: The correct answer is 'meter.' In the metric system, 'm' stands for meter, which is the base unit for length. Choice B, 'mole,' is a unit used in chemistry to represent an amount of substance. Choice C, 'milli,' represents a prefix indicating one-thousandth, and choice D, 'micro,' represents a prefix indicating one-millionth. Therefore, the correct choice is 'A: meter.'

Correct Answer: B

Rationale: To convert kiloliters to liters, you multiply by 1,000. Therefore, 1 kiloliter 1,000 = 1,000 liters. Choice A (100 liters) is incorrect because it represents only 1/10th of a kiloliter. Choice C (10 liters) is incorrect as it represents only 1/100th of a kiloliter. Choice D (10,000 liters) is incorrect as it is 10 times bigger than a kiloliter.

Correct Answer: B

Rationale: To convert centimeters to kilometers, you need to divide by 100,000 since there are 100,000 centimeters in a kilometer. Therefore, 345 cm · 100,000 = 0.00345 km. The correct answer is 0.0345 km, which is obtained by accurately dividing 345 by 100,000. Choices A, C, and D are incorrect because they do not correctly apply the conversion factor and result in inaccurate values for kilometers.