Correct Answer: B

Rationale: The correct answer is B: 0.1 cm. One millimeter is equal to 0.1 centimeters, not 1/100th cm as mentioned in choice A. Choice C, 1 cm, is incorrect as a millimeter is smaller than a centimeter. Choice D, 10 cm, is incorrect as it incorrectly magnifies the conversion, making a millimeter larger than a centimeter. Therefore, the accurate conversion is that one millimeter equals 0.1 centimeters.

Correct Answer: B

Rationale: To convert milliliters to liters, you need to divide by 1000 since there are 1000 milliliters in a liter. Therefore, 250 milliliters is equal to 250/1000 = 0.25 liters. Choice A, 25 liters, is incorrect as it is a magnitude higher than the correct answer. Choice C, 2.5 liters, is also incorrect as it is 10 times greater than the correct conversion. Choice D, 0.025 liters, is incorrect as it is a magnitude lower than the correct conversion.

Correct Answer: A

Rationale: To find the product of 0.5 and 20, you multiply them together. 0.5 x 20 = 10. This calculation involves multiplying a decimal (0.5) by a whole number (20). Choice A, '10', is the correct answer. Choice B, '15', is incorrect as it does not accurately represent the result of multiplying 0.5 by 20. Choices C and D, '20' and '25', are also incorrect as they do not reflect the correct calculation. This question assesses your ability to perform basic arithmetic operations involving decimals and whole numbers.

Correct Answer: B

Rationale: To convert 0.1 liter to milliliters, you need to multiply by 1000 because there are 1000 milliliters in a liter. Therefore, 0.1 liter converts to 100 milliliters. Choice A (10 ml) is incorrect as it represents 0.01 liters, not 0.1 liters. Choice C (1000 ml) is incorrect as it represents 1 liter, not 0.1 liters. Choice D (1 ml) is incorrect as it is too small a quantity for 0.1 liters.

Correct Answer: C

Rationale: The correct answer is C: 0.13 inches. When converting decimals to inches, the value remains the same. Choice A, 0.013 inches, represents a smaller value than 0.13 inches as it has an extra zero. Choice B, 1.3 inches, is incorrect as it is a larger value than 0.13 inches. Choice D, 13 inches, is significantly larger than 0.13 inches, making it an incorrect conversion.