Correct Answer: C

Rationale: The correct answer is C: 0.45. To find the result of multiplying 0.15 by 3, you simply multiply the two numbers together, which gives you 0.45. Choice A (0.05) is incorrect as it is the result of dividing 0.15 by 3 instead of multiplying. Choice B (0.15) is the original number being multiplied and not the result. Choice D (0.45) is the same as the correct answer but is repeated for redundancy.

Correct Answer: A

Rationale: The correct answer is A: 2.54 cm. One inch is equivalent to 2.54 centimeters. This conversion factor is commonly used when converting measurements between the metric and imperial systems. Choice B (3 cm) is incorrect as it is not the accurate conversion factor for 1 inch. Choice C (2 cm) is also incorrect as it does not reflect the correct conversion. Choice D (1 cm) is incorrect as it inaccurately states the conversion value for 1 inch.

Correct Answer: B

Rationale: The metric system is based on powers of 10. This means that units within the system are related by factors of 10, making conversions straightforward by simply shifting the decimal point. The system's simplicity and consistency are derived from this fundamental concept. Choices A, C, and D are incorrect because the metric system's foundation lies in the consistent relationship between units through powers of 10, not through basic arithmetic operations like multiplication, addition, or subtraction.

Correct Answer: B

Rationale: The correct answer is B: 5280 feet. One mile is equivalent to 5280 feet. This is a standard conversion that is widely known. Choice A (5000 feet) is incorrect as it is not the exact conversion of a mile. Choice C (5300 feet) and choice D (5500 feet) are also incorrect as they do not represent the accurate conversion from miles to feet.

Correct Answer: A

Rationale: The correct answer is A: 298.15 K. The conversion from Celsius to Kelvin is K = C + 273.15. Therefore, 25°C is equivalent to 298.15 K, as 25 + 273.15 = 298.15. Choice B, 273.15 K, is the freezing point of water in Kelvin, not the equivalent of 25°C. Choice C, 250 K, and Choice D, 25 K, are incorrect conversions and do not align with the correct formula for converting Celsius to Kelvin.