Correct Answer: A

Rationale: To convert 0.004 to a ratio, we first express it as 4/1000, which simplifies to 1/250. Hence, 0.004 is equivalent to the simplified ratio of 1:250. Choice B, 4:35, is incorrect as it does not reflect the correct conversion. Choice C, 7:28, is incorrect because it does not represent the simplified ratio of 0.004. Choice D, 4:00, is incorrect as it does not simplify to the original decimal value.

Correct Answer: A

Rationale: To convert 0.004 to a ratio, we can express it as 4/1000, which simplifies to 1/250. Therefore, the correct ratio is 1:250. Choice B (4:200) is incorrect as it simplifies to 1:50, not 1:250. Choice C (2:400) simplifies to 1:200, which is also incorrect. Choice D (9:200) simplifies to a ratio greater than 1:1, which is not equivalent to 1:250.

Correct Answer: B

Rationale: To convert kiloliters to liters, you multiply by 1,000. Therefore, 1 kiloliter 1,000 = 1,000 liters. Choice A (100 liters) is incorrect because it represents only 1/10th of a kiloliter. Choice C (10 liters) is incorrect as it represents only 1/100th of a kiloliter. Choice D (10,000 liters) is incorrect as it is 10 times bigger than a kiloliter.

Correct Answer: B

Rationale: To convert meters to centimeters, you need to multiply by 100 since there are 100 centimeters in a meter. Therefore, 0.25 meters x 100 = 25 centimeters. Choice A, '2.5 cm,' is incorrect as it is the result of multiplying by 10 instead of 100. Choice C, '250 cm,' is incorrect as it is the result of multiplying by 1000. Choice D, '0.25 cm,' is incorrect as it suggests the conversion is in the opposite direction, from centimeters to meters.

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.