Correct Answer: B

Rationale: 0.3 milliliters is equivalent to 0.3 ml. This is a precise measurement commonly used in medical settings for administering small doses of liquid medication. It is important to understand and recognize the decimal point placement when converting between milliliters and other volume units. Choice A (0.03 ml) is incorrect as it represents a smaller amount than 0.3 ml. Choice C (3 ml) and Choice D (30 ml) are also incorrect as they are larger measurements and do not match the given amount of 0.3 ml.

Correct Answer: B

Rationale: The correct answer is B: '0.001 m.' The prefix 'milli' represents a factor of 10^-3, which means one millimeter (mm) is equivalent to 0.001 meters (m). Therefore, 1 mm is equal to 0.001 m. Choice A, '0.01 m,' is incorrect as it represents 0.01 meters, not 0.001 meters. Choice C, '0.1 m,' is incorrect because it stands for 0.1 meters, which is 10 times greater than 1 mm. Choice D, '1 m,' is incorrect as it represents 1 meter, which is 1000 times greater than 1 mm.

Correct Answer: B

Rationale: To convert centimeters to kilometers, you need to divide by 100,000 since there are 100,000 centimeters in a kilometer. Therefore, 345 cm · 100,000 = 0.00345 km. The correct answer is 0.0345 km, which is obtained by accurately dividing 345 by 100,000. Choices A, C, and D are incorrect because they do not correctly apply the conversion factor and result in inaccurate values for kilometers.

Correct Answer: A

Rationale: The prefixes 'micro-' and 'milli-' represent 10^-6 and 10^-3, respectively. 'Micro-' denotes one-millionth (10^-6), while 'milli-' denotes one-thousandth (10^-3). Choice B is incorrect because it confuses the order of magnitudes for micro and milli. Choice C and D are also incorrect as they provide the wrong values for the prefixes micro and milli.

Correct Answer: B

Rationale: 0.3 milliliters is equivalent to 0.3 ml. This is a precise measurement commonly used in medical settings for administering small doses of liquid medication. It is important to understand and recognize the decimal point placement when converting between milliliters and other volume units. Choice A (0.03 ml) is incorrect as it represents a smaller amount than 0.3 ml. Choice C (3 ml) and Choice D (30 ml) are also incorrect as they are larger measurements and do not match the given amount of 0.3 ml.