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.

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: B

Rationale: The correct answer is B: 0.16 inches. This value is already in its simplest form and represents sixteen one-hundredths of an inch. Choice A, 0.016 inches, is incorrect as it represents sixteen thousandths of an inch, not the given value. Choice C, 1.6 inches, is incorrect as it represents one and six-tenths inches, which is larger than the given value. Choice D, 16 inches, is incorrect as it represents sixteen inches, which is significantly larger than the given value of 0.16 inches.

Correct Answer: A

Rationale: To convert milligrams to micrograms, you need to multiply by 1000 because there are 1000 micrograms in 1 milligram. Therefore, 0.15 mg is equal to 150 mcg. Choice B (15 mcg) is incorrect as it represents the conversion of 0.015 mg to mcg. Choice C (1.5 mcg) is incorrect as it represents the conversion of 0.0015 mg to mcg. Choice D (1500 mcg) is incorrect as it represents the conversion of 1.5 mg to mcg. So, the correct answer is 150 mcg, a conversion often used in medical dosing.

Correct Answer: B

Rationale: To convert meters to millimeters, you need to multiply by 1,000 because there are 1,000 millimeters in a meter. Therefore, 3.45 meters 1,000 = 3,450 millimeters. Choices A, C, and D are incorrect because they do not reflect the correct conversion factor from meters to millimeters.