How many centimeters are in 0.25 meters?

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: The correct answer is B: 2 liters. To convert milliliters to liters, you need to divide by 1000 since there are 1000 milliliters in a liter. Therefore, 2,000 milliliters is equal to 2 liters (2000 · 1000 = 2). Choices A, C, and D are incorrect because they incorrectly convert milliliters to liters, resulting in values that are too low (A and C) or too high (D).

Correct Answer: A

Rationale: To convert liters to milliliters, you need to multiply by 1000 since 1 liter equals 1000 milliliters. Therefore, 0.45 liters is equivalent to 450 milliliters. Choice B, 45 ml, is incorrect as it represents the conversion of 0.045 liters to milliliters. Choice C, 4.5 ml, is incorrect as it represents the conversion of 0.0045 liters to milliliters. Choice D, 0.45 ml, is incorrect as it is the initial quantity in milliliters and not the result of the conversion.

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, 35.4 cm · 100,000 = 0.000354 km. Choice A (0.00354 km) is incorrect as it represents dividing by 10,000, not 100,000. Choice C (0.00345 km) is incorrect as the last digit is different from the correct answer. Choice D (0.0345 km) is incorrect as it represents dividing by 1,000, not by 100,000.

Correct Answer: A

Rationale: The correct answer is A: 1760 yards. There are 1760 yards in one mile. This conversion is a standard unit of measurement in the imperial system. Choice B, 1500 yards, is incorrect as it is not the correct conversion from miles to yards. Choice C, 2000 yards, is also incorrect as it does not represent the accurate conversion. Choice D, 1800 yards, is incorrect as it does not reflect the correct number of yards in a mile according to the established conversion rate.

Correct Answer: B

Rationale: The decimal 0.2 is already at the nearest tenth, so it does not need to be rounded. Rounding to the nearest tenth means keeping one decimal place, which is already the case with 0.2. Therefore, the correct answer is 0.2, as it is already at the specified rounding point. Choices A, C, and D are incorrect because they represent values that are not the result of rounding 0.2 to the nearest tenth. 0.1 is rounding down, 0.3 is rounding up, and 0.25 is not the nearest tenth of 0.2.

Correct Answer: B

Rationale: To convert liters to milliliters, you need to multiply by 1,000 because there are 1,000 milliliters in 1 liter. Therefore, 3,540 liters 1,000 = 3,540,000 milliliters. Choices A, C, and D are incorrect because they do not correctly convert liters to milliliters. A, C, and D are off by a factor of 1,000, as they do not account for the conversion factor between liters and milliliters.

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.

Correct Answer: A

Rationale: The correct answer is 'meter.' In the metric system, 'm' stands for meter, which is the base unit for length. Choice B, 'mole,' is a unit used in chemistry to represent an amount of substance. Choice C, 'milli,' represents a prefix indicating one-thousandth, and choice D, 'micro,' represents a prefix indicating one-millionth. Therefore, the correct choice is 'A: meter.'