Correct Answer: A

Rationale: To convert milligrams to micrograms, you need to multiply by 1000. Therefore, 0.1 mg is equal to 100 mcg. This conversion is commonly used in medical calculations. Choice B (10 mcg) is incorrect because it would be the conversion from milligrams to micrograms if multiplied by 100, not 10. Choice C (1000 mcg) is incorrect as it would be the conversion from grams to micrograms if multiplied by 1000. Choice D (1 mcg) is incorrect as it represents the original unit without conversion.

Correct Answer: D

Rationale: The correct answer is D: 1,000 µg. To convert milligrams to micrograms, you need to multiply by 1,000 because there are 1,000 micrograms in 1 milligram. Choices A, B, and C are incorrect because they do not correctly convert milligrams to micrograms. 1 milligram is equal to 1,000 micrograms, making choice D the right answer.

Correct Answer: B

Rationale: To convert milligrams to grams, you need to divide by 1,000 because there are 1,000 milligrams in a gram. Therefore, 35,400 mg · 1,000 = 35.4 grams. Choice A is incorrect because it does not account for the conversion from milligrams to grams. Choice C is incorrect as it incorrectly drops a zero, leading to an inaccurate conversion. Choice D is incorrect as it incorrectly multiplies instead of dividing, resulting in a significantly larger value than the correct answer.

Correct Answer: A

Rationale: To convert 0.04 grams to milligrams, you need to multiply by 1000, not 10000. Therefore, 0.04 grams equals 40 milligrams (0.04g * 1000 = 40mg). Choice B, '4 mg,' is incorrect as it reflects the value as if it was in grams. Choice C, '400 mg,' is incorrect as it incorrectly multiplies by 100 instead of 1000. Choice D, '0.4 mg,' is incorrect as it incorrectly moves the decimal point to the right instead of multiplying by 1000.

Correct Answer: B

Rationale: To convert liters to milliliters, you need to multiply by 1000 since there are 1000 milliliters in 1 liter. Therefore, 0.5 liters x 1000 = 500 milliliters, making choice B the correct answer. Choices A, C, and D are incorrect because they do not correctly convert liters to milliliters.