Correct Answer: C

Rationale: To convert centimeters to millimeters, you need to multiply by 10 since there are 10 millimeters in a centimeter. Therefore, 0.75 centimeters equals 0.75 x 10 = 7.5 millimeters, not 75 millimeters (Choice C). Choice A (7.5 mm) is the correct conversion, while Choice B (0.75 mm) and Choice D (75 cm) are incorrect conversions.

Correct Answer: A

Rationale: To convert 0.04 grams to milligrams, you need to multiply by 1000, not 10000. Therefore, 0.04 grams equals 40 milligrams (0.04g * 1000 = 40mg). Choice B, '4 mg,' is incorrect as it reflects the value as if it was in grams. Choice C, '400 mg,' is incorrect as it incorrectly multiplies by 100 instead of 1000. Choice D, '0.4 mg,' is incorrect as it incorrectly moves the decimal point to the right instead of multiplying by 1000.

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: A

Rationale: The correct answer is A: 1 kilometer. 10^6 meters is equivalent to 1 kilometer, not 1 megameter. The prefix 'kilo-' represents a factor of 10^3 or one thousand, which is the appropriate conversion in this case. Choice B, 1 megameter, would be 10^6 meters squared. Choices C and D, 1 gigameter and 1 terameter, would represent even larger distances, as 'giga-' represents 10^9 and 'tera-' represents 10^12.

Correct Answer: A

Rationale: The correct answer is A: 9. To find the result of multiplying 0.15 by 60, you simply multiply the two numbers together. 0.15 * 60 = 9. This calculation involves basic multiplication. Choices B, C, and D are incorrect as they do not reflect the correct product of 0.15 and 60. Understanding how to multiply decimals and whole numbers is essential in various real-life scenarios such as calculating percentages or adjusting measurements.