Correct Answer: C

Rationale: To calculate the total time, first find the time for the first leg of the trip: 305 miles / 65 mph = 4.69 hours. Then, add the time for the second leg: 162 miles / 80 mph = 2.025 hours. Next, add the 15-minute stop in hours (15 minutes = 0.25 hours). Finally, add the times together: 4.69 hours + 2.025 hours + 0.25 hours = 6.965 hours, which rounds to 6.69 hours. Therefore, the correct answer is 6.69 hours. Choice A is incorrect because it does not account for the total driving time correctly. Choice B is incorrect as it does not include the time for the gas station stop. Choice D is wrong as it miscalculates the total time taken for the trip.

Correct Answer: C

Rationale: To calculate the total time, first find the time for the first leg of the trip: 305 miles / 65 mph = 4.69 hours. Then, add the time for the second leg: 162 miles / 80 mph = 2.025 hours. Next, add the 15-minute stop in hours (15 minutes = 0.25 hours). Finally, add the times together: 4.69 hours + 2.025 hours + 0.25 hours = 6.965 hours, which rounds to 6.69 hours. Therefore, the correct answer is 6.69 hours. Choice A is incorrect because it does not account for the total driving time correctly. Choice B is incorrect as it does not include the time for the gas station stop. Choice D is wrong as it miscalculates the total time taken for the trip.

Correct Answer: C

Rationale: To find the correct dosage in milliliters, divide the total required dosage in milligrams (240 mg) by the concentration of the medication in milligrams per milliliter (20 mg/mL). This calculation yields 12 mL, which is the recommended volume for the child. Choice A, 0.8 mL, is incorrect as it does not correspond to the correct dosage. Choice B, 1.6 mL, is incorrect because it also does not match the calculated dosage. Choice D, 3.2 mL, is incorrect as it is not the accurate result of the dosage calculation. Therefore, the correct answer is C, 2.4 mL.

Correct Answer: C

Rationale: To find the number of questions answered correctly, you multiply the percentage (85%) by the total number of questions (50). 85% of 50 questions is 0.85 * 50 = 43 questions answered correctly. Therefore, the correct answer is 43 questions. Choices A, B, and D are incorrect as they do not reflect the accurate calculation based on the given information.

Correct Answer: B

Rationale: To find the number of girls in the class, we need to calculate 40% of the total number of students, which is 30. 40% of 30 is 0.40 * 30 = 12 girls. Therefore, there are 12 girls in the class. Choice A, 18 girls, is incorrect as it miscalculates the percentage. Choice C, 15 girls, is incorrect as it misrepresents the correct calculation. Choice D, 10 girls, is incorrect as it underestimates the number of girls in the class.