Correct Answer: A

Rationale: To convert 0.875 to a fraction, express it as 875\10000. Simplifying this fraction by dividing both the numerator and denominator by 125 results in 7\80.

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: A

Rationale: To convert liters to milliliters, you need to multiply by 1000 since 1 liter is equal to 1000 milliliters. Therefore, 0.5 liters equals 500 milliliters. This conversion is commonly used in various fields such as cooking, medicine, and science. Choice B, 50 ml, is incorrect as it represents 0.05 liters, not 0.5 liters. Choice C, 5 ml, is even smaller and represents 0.005 liters. Choice D, 0.5 ml, is incorrect as it is a tenth of the correct conversion.

Correct Answer: B

Rationale: To convert kilograms to grams, you need to multiply by 1,000 since 1 kilogram is equal to 1,000 grams. Therefore, 0.0345 kg multiplied by 1,000 equals 34.5 grams. Choices A, C, and D are incorrect because they do not correctly convert kilograms to grams. A states 3.45 grams, which is off by a factor of 10. C and D overestimate the conversion by considering the decimal point in the original value as a whole number. Hence, the correct answer is B, 34.5 grams.

Correct Answer: A

Rationale: To convert milliliters to liters, you need to divide by 1000 since there are 1000 milliliters in a liter. Therefore, 2500 milliliters divided by 1000 equals 2.5 liters, making choice A the correct answer. Choice B is incorrect because it incorrectly multiplies instead of dividing. Choice C is incorrect as it incorrectly places the decimal point, resulting in an incorrect conversion. Choice D is incorrect as it multiplies instead of dividing, leading to an inaccurate conversion.