A lab technician took 100 hairs from a patient to conduct several tests. The technician used 1/7 of the hairs for a drug test. How many hairs were used for the drug test? (Round your answer to the nearest hundredth.)

Correct Answer: C

Rationale: To find how many hairs were used for the drug test, you need to calculate 1/7 of 100. 1/7 of 100 is 14.2857, which rounds to 14.29 when rounded to the nearest hundredth. Therefore, 14.29 hairs were used for the drug test. Choice A is incorrect as it does not account for rounding to the nearest hundredth. Choices B and D are incorrect as they do not accurately reflect the calculated value after rounding.

Correct Answer: A

Rationale: To determine the order from least to greatest, convert all the values to a common form. When written in decimal form, the order is -2, -0.75 (which is equal to -3/4), -0.45, 0.03 (which is equal to 3%), and 0.36. Therefore, the correct order is -2, -3/4, -0.45, 3%, 0.36 (Choice A). Choice B is incorrect as it has the incorrect placement of -2 and 0.36. Choice C is incorrect as it incorrectly places -0.45 before -2. Choice D is incorrect as it incorrectly places 0.36 before 3%.

Correct Answer: C

Rationale: To find the mean time, you need to add all the times (22.33 + 22.50 + 22.50 + 22.61 + 22.71 + 22.72 + 22.83 + 23.22) and then divide by the total number of times (8). This calculation results in a mean time of 22.68 seconds. Choice A, 22.50 sec, is incorrect because it is the time of one of the runners, not the mean time. Choice B, 22.66 sec, and Choice D, 22.77 sec, are also incorrect as they are not the calculated mean of the given times.

Correct Answer: A

Rationale: To find the volume of the aquarium, we multiply its length, width, and height. The formula for the volume of a rectangular solid is V = l w h. Substituting the given dimensions, we get V = 30 10 12 = 3600 cubic inches. Therefore, the aquarium can hold 3600 cubic inches of water. Choice B (52 cubic inches), Choice C (312 cubic inches), and Choice D (1144 cubic inches) are incorrect as they do not correctly calculate the volume of the aquarium based on its dimensions.

Correct Answer: D

Rationale: To convert grams to milligrams, you need to multiply by 1000 since 1 gram is equal to 1000 milligrams. Therefore, 5 grams is equal to 5 * 1000 = 5000 milligrams. Choices A, B, and C are incorrect because they do not correctly convert grams to milligrams. Choice A is incorrect as it represents a decrease in value instead of an increase when converting from grams to milligrams. Choice B is incorrect because it is a factor of 10 lower than the correct answer. Choice C is incorrect as it is a factor of 10 lower than the correct answer. Thus, the correct answer is D, 5000 mg.