Correct Answer: A

Rationale: The least common multiple is the smallest number that both numbers multiply into, which means it is the smallest number that both numbers can be evenly divided by without leaving a remainder. The least common factor, on the other hand, is the smallest number that divides both numbers without leaving a remainder. Therefore, choice A is correct as it accurately defines the least common multiple and factor. Choices B, C, and D are incorrect because they provide inaccurate definitions or mix up the concepts of multiplication and division in relation to finding the least common multiple and factor.

Correct Answer: D

Rationale: The correct answer is D: 17.8 cm. To convert inches to centimeters, you can use the conversion factor 1 inch = 2.54 cm. Therefore, 7 inches is equal to 7 * 2.54 = 17.78 cm, which rounds to 17.8 cm. Choices A, B, and C are incorrect because they do not correspond to the correct conversion of 7 inches to centimeters.

Correct Answer: B

Rationale: To find the number of students enrolled in the respiratory care program, you need to calculate 19% of 800. 19% of 800 is (19/100) * 800 = 152 students. Therefore, the correct answer is B. Choice A (336), Choice C (144), and Choice D (168) are incorrect as they do not represent the correct percentage of students enrolled in the respiratory care program as indicated by the pie chart.

Correct Answer: A

Rationale: To find the area of the soccer field, multiply its length by its width: 100 meters 75 meters = 7500 square meters. To convert this to hectares, divide by 10,000 (since 1 hectare = 10,000 square meters), resulting in 0.75 hectares. Therefore, the correct answer is A. Choices B, C, and D are incorrect because they do not correctly convert the area to hectares. B and C are off by a factor of 10, while D is off by a factor of 10,000.

Correct Answer: C

Rationale: A composite number is a positive integer greater than one that has more than two factors. Choice A is incorrect because a number with only two factors is a prime number. Choice B is incorrect as being a fraction does not define a composite number. Choice D is incorrect because a number with exactly two factors is a prime number, not a composite number.