Correct Answer: B

Rationale: To convert 0.2 liters to milliliters, you need to multiply by 1,000 because there are 1,000 milliliters in a liter. So, 0.2 * 1,000 = 200 milliliters. Therefore, the correct answer is 200 ml. Choice A (20 ml) is incorrect because it represents 0.02 liters, not 0.2 liters. Choice C (2 ml) is incorrect as it represents 0.002 liters. Choice D (2000 ml) is incorrect as it represents 2 liters, not 0.2 liters.

Correct Answer: A

Rationale: To convert liters to milliliters, you need to multiply by 1,000 since there are 1,000 milliliters in a liter. So, to convert 0.04 liters to milliliters, you would multiply 0.04 by 1,000, giving you 40 milliliters. This means that choice A, '40 ml', is the correct answer. Choices B, C, and D are incorrect because they do not correctly convert liters to milliliters. Choice B, '4 ml', is incorrect as it is 10 times smaller than the correct conversion. Choice C, '400 ml', is incorrect as it is 10 times larger than the correct conversion. Choice D, '0.4 ml', is incorrect as it is one-tenth of the correct conversion.

Correct Answer: B

Rationale: To convert kilograms to grams, you need to multiply by 1,000 since there are 1,000 grams in a kilogram. Therefore, 35.40 kg 1,000 = 35,400 grams. Choice A (354 g) is incorrect because it is off by a factor of 10. Choice C (3,540 g) is incorrect as it is off by a factor of 100. Choice D (3.54 g) is incorrect as it represents kilograms instead of grams.

Correct Answer: A

Rationale: Density is measured in grams per cubic meter (g/m³) in the metric system. This unit represents the amount of mass (in grams) per unit volume (cubic meter). Choice B, grams per liter (g/L), is incorrect as density is not typically measured in liters. Choice C, grams per cubic centimeter (g/cm³), is a common unit for density but not the standard SI unit. Choice D, grams per square meter (g/m²), is a unit for surface density, not volumetric density. Therefore, the correct unit for measuring density in the metric system is grams per cubic meter (g/m³).

Correct Answer: A

Rationale: To convert micrograms (mcg) to milligrams (mg), you need to divide by 1000. Therefore, 0.05 mcg equals 0.00005 mg. This conversion is crucial in the medical field to ensure accurate dosing. Choice B, 0.0005 mg, is incorrect as it represents 0.5 mcg. Choice C, 0.005 mg, is the equivalent of 5 mcg. Choice D, 0.05 mg, actually represents 50 mcg. It's important to pay attention to decimal placement and unit conversions to avoid medication errors.