Correct Answer: B

Rationale: To convert kilometers to meters, you need to multiply by 1,000 since there are 1,000 meters in 1 kilometer. Therefore, 0.345 km 1,000 = 345 meters. Choice A (3.45 m) is incorrect because it is the result of a mathematical error; the decimal point was misplaced. Choice C (345 cm) is incorrect as it represents centimeters, not meters. Choice D (345 m) is a duplicate of the correct answer B.

Correct Answer: A

Rationale: To convert liters to ounces, you need to multiply the liter value by 33.814. Therefore, to convert 0.5 liters to ounces, you would calculate 0.5 x 33.814 = 16.91 ounces. This conversion factor is commonly used in cooking and liquid measurements. Choice B, C, and D are incorrect as they do not reflect the accurate conversion from liters to ounces.

Correct Answer: B

Rationale: To convert grams to milligrams, you need to multiply by 1,000 because there are 1,000 milligrams in 1 gram. Therefore, 1 gram 1,000 = 1,000 milligrams. Choice A (100 mg) is incorrect as it represents 0.1 grams, not 1 gram. Choice C (1 mg) is incorrect as it represents a fraction of a gram. Choice D (10,000 mg) is incorrect as it is 10 times more than the correct conversion.

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: B

Rationale: To convert liters to milliliters, you need to multiply by 1000, not 10000. Therefore, 0.2 liters equals 200 ml (0.2 x 1000 = 200 ml). Choice A, 20 ml, is incorrect because it's the result of multiplying by 10 instead of 1000. Choice C, 2 ml, is incorrect as it's the result of ignoring the decimal point. Choice D, 2000 ml, is incorrect because it's the result of multiplying by 10000.