Nursing Metric Conversions

Correct Answer: A

Rationale: The correct answer is A: kilometer. In the metric system, 'km' stands for kilometer, which is a unit of length equal to 1000 meters. This is because the prefix 'kilo-' signifies a factor of 1000. Kilomole (B) is not a standard metric unit. Kilobyte (C) is a unit of digital information storage, not length. Knot (D) is a unit of speed typically used in maritime and aviation contexts, not length. Therefore, A is the correct choice for 'km' in the metric system.

Correct Answer: A

Rationale: To convert liters to milliliters, you need to multiply by 1000 since there are 1000 milliliters in 1 liter. Therefore, to find how many milliliters are in 0.5 liters, you would multiply 0.5 by 1000 which equals 500 ml. This makes choice A, 500 ml, the correct answer. Choices B, C, and D are incorrect because they do not correctly convert liters to milliliters. Choice B (50 ml) is 10 times less than the correct answer, choice C (5 ml) is 100 times less, and choice D (0.5 ml) is 1000 times less than the correct answer.

Correct Answer: D

Rationale: To convert mg to mcg, we need to multiply by 1000 since 1 mg = 1000 mcg. So, 0.075 mg x 1000 = 75 mcg. Therefore, the correct answer is D: 750 mcg. The other choices are incorrect because they do not correctly convert milligrams to micrograms. A, B, and C are not the correct conversion of 0.075 mg to mcg.

Correct Answer: B

Rationale: The correct answer is B: derived units. Derived units are formed when base units are combined using mathematical operations. In the case of g/mL for density, grams (g) and milliliters (mL) are base units that are combined to express the derived unit of density. This combination involves division to represent the mass per unit volume. Therefore, derived units are the appropriate term for such combinations. Summary: A: Combined units is a vague term and does not specifically refer to the mathematical combination of base units. C: Base units refer to the fundamental units from which derived units are formed, but they are not the combination of base units. D: Calculated units do involve mathematical operations, but they do not specifically refer to the combination of base units to form derived units.

Correct Answer: B

Rationale: To convert centimeters to kilometers, we need to divide by 100,000 (since 1 kilometer = 100,000 centimeters). For 345 cm, the correct calculation is 345 / 100,000 = 0.00345 km. The correct answer is B (0.0345 km) because of a common error in decimal placement. Option A is incorrect as it has an extra zero. Option C is incorrect as it is off by a factor of 10. Option D is incorrect as it is off by a factor of 100.