Correct Answer: B

Rationale: The correct answer is B: 30 ml. 1 ounce is equivalent to 30 milliliters. This conversion is a common one in many contexts involving liquid measurements. Choice A (20 ml), Choice C (40 ml), and Choice D (50 ml) are incorrect conversions and do not represent the accurate conversion between ounces and milliliters.

Correct Answer: A

Rationale: To convert liters to quarts, we know that 1 liter is approximately equal to 1.06 quarts. Therefore, 2 liters would be around 2.12 quarts. However, for practical purposes, it's often rounded to 2.1 quarts. Option A, '1.06 quarts,' is the closest and most accurate approximation. Option B, '0.5 quarts,' is incorrect as it represents half of the actual conversion. Option C, '2.1 quarts,' is close but slightly higher than the actual conversion. Option D, '4 quarts,' is double the correct conversion and is therefore incorrect.

Correct Answer: B

Rationale: To convert milligrams to micrograms, you need to multiply by 1000 since 1 mg is equal to 1000 mcg. Therefore, 0.2 mg is equivalent to 200 mcg. It is crucial to understand this conversion to ensure precise medication dosages. Choice A is incorrect because it does not account for the conversion factor of 1000 between milligrams and micrograms. Choice C is incorrect as it represents the conversion of grams to micrograms. Choice D is incorrect as it does not consider the conversion factor from milligrams to micrograms.

Correct Answer: B

Rationale: The prefix 'milli' means one-thousandth, which is equivalent to 0.001 of the base unit. For instance, 1 millimeter is equal to 0.001 meters. Choice A (0.01) is incorrect as it represents one-hundredth, not one-thousandth. Choice C (0.0001) is incorrect as it signifies ten-thousandth, not one-thousandth. Choice D (0.00001) is incorrect as it stands for one-hundred-thousandth, not one-thousandth.

Correct Answer: A

Rationale: To find the product of 0.5 and 200, you multiply the two numbers, which equals 100. The correct answer is A. Choice B, 50, is the result of multiplying 0.5 by 100 instead of 200. Choice C, 150, is the result of adding 0.5 and 200 instead of multiplying them. Choice D, 200, is the second number in the multiplication operation and not the correct product.