Correct Answer: B

Rationale: The correct answer is B: 2.54 cm. One inch is equivalent to 2.54 centimeters in the metric system. This conversion factor is commonly used in converting measurements between the imperial and metric systems. Choice A (1.54 cm), Choice C (3.54 cm), and Choice D (4.54 cm) are incorrect conversions and do not represent the accurate metric equivalent of 1 inch.

Correct Answer: A

Rationale: The decimal 0.07 can be expressed as the fraction 7/100, where 7 is the numerator and 100 is the denominator. To simplify the fraction, you divide both the numerator and denominator by their greatest common divisor, which in this case is 1. Therefore, 7/100 is already in its simplest form and cannot be further simplified. Choices B, C, and D are incorrect fractions as they do not represent the decimal 0.07.

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: C

Rationale: The prefix 'femto-' stands for 10^-15, making femtometer equal to 10^-15 meters. The incorrect choices are A and B because 'pico-' represents 10^-12 (picometer) and 'nano-' represents 10^-9 (nanometer), respectively. Choice D is also incorrect as 'pico-' is associated with 10^-12, not 10^-15.

Correct Answer: A

Rationale: To convert milligrams (mg) to micrograms (mcg), you multiply by 1000 because 1 mg is equal to 1000 mcg. Therefore, 0.25 mg is equal to 250 mcg. Choices B, C, and D are incorrect as they do not consider the correct conversion factor.