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.

Correct Answer: C

Rationale: To convert kilograms to grams, you need to multiply by 1000 because there are 1000 grams in a kilogram. Therefore, 5 kilograms x 1000 grams/kilogram = 5000 grams. Choices A, B, and D are incorrect because they do not correctly convert kilograms to grams.

Correct Answer: A

Rationale: To convert a decimal to a fraction, you can write the decimal as a fraction with the decimal part as the numerator and a power of 10 as the denominator. In this case, 0.75 can be written as 75/100. Simplifying this fraction by dividing both the numerator and denominator by 25 gives you 3/4. Therefore, the correct answer is A. Choice B (7/10), Choice C (15/20), and Choice D (1/2) are incorrect because they do not represent the correct conversion of 0.75 into a fraction.

Correct Answer: A

Rationale: To convert milligrams (mg) to micrograms (mcg), you need to multiply by 1000 since 1 mg is equal to 1000 mcg. Therefore, 0.3 mg x 1000 = 300 mcg. This conversion is crucial in healthcare to ensure accurate medication dosages. Choice B (30 mcg) is incorrect as it represents the conversion of 0.03 mg to mcg. Choice C (3000 mcg) is incorrect as it is the result of multiplying 0.3 mg by 10 instead of 1000. Choice D (3 mcg) is incorrect as it is the result of not multiplying by 1000 to convert milligrams to micrograms.

Correct Answer: A

Rationale: 'kg' stands for kilogram, the unit of mass equal to 1,000 grams. In the metric system, 'kg' specifically represents the unit of mass, making 'kilogram' the correct choice. The other choices, 'keg,' 'kroner,' and 'kraken,' do not represent the standard unit of mass in the metric system and are therefore incorrect.