Correct Answer: A

Rationale: To convert liters to milliliters, you need to multiply by 1000 since 1 liter equals 1000 milliliters. Therefore, 0.45 liters is equivalent to 450 milliliters. Choice B, 45 ml, is incorrect as it represents the conversion of 0.045 liters to milliliters. Choice C, 4.5 ml, is incorrect as it represents the conversion of 0.0045 liters to milliliters. Choice D, 0.45 ml, is incorrect as it is the initial quantity in milliliters and not the result of the conversion.

Correct Answer: A

Rationale: 0.05 mg is equivalent to 50 mcg because 1 mg is equal to 1000 mcg. To convert milligrams to micrograms, you need to multiply by 1000. Therefore, 0.05 mg x 1000 = 50 mcg. Choices B, C, and D are incorrect because they do not correctly convert milligrams to micrograms. Option B (500 mcg) would be the result if the conversion was done incorrectly by adding an extra zero, while options C (5 mcg) and D (0.5 mcg) are incorrect due to miscalculating the conversion factor.

Correct Answer: B

Rationale: The correct answer is B: 2 liters. To convert milliliters to liters, you need to divide by 1000 since there are 1000 milliliters in a liter. Therefore, 2,000 milliliters is equal to 2 liters (2000 · 1000 = 2). Choices A, C, and D are incorrect because they incorrectly convert milliliters to liters, resulting in values that are too low (A and C) or too high (D).

Correct Answer: A

Rationale: To convert centimeters to millimeters, you need to multiply by 10 since 1 centimeter equals 10 millimeters. Therefore, 0.5 centimeters is equal to 5 millimeters (0.5 * 10 = 5). Choice A, '5 mm,' is the correct answer. Choice B, '0.5 mm,' is incorrect as it would be equivalent to half a millimeter. Choice C, '50 mm,' is incorrect as it represents 50 millimeters, which would be the equivalent of 5 centimeters. Choice D, '0.05 mm,' is incorrect as it represents 0.05 millimeters, which is a fraction of 1 millimeter.

Correct Answer: B

Rationale: To convert kilograms to grams, you need to multiply by 1000 since there are 1000 grams in a kilogram. Therefore, 2 kilograms is equal to 2 x 1000 = 2000 grams. Choice A (200 grams) is incorrect as it represents the value of 0.2 kilograms. Choice C (20 grams) is incorrect as it represents the value of 0.02 kilograms. Choice D (2 grams) is incorrect as it represents the value of 0.002 kilograms.