A team from the highway department can replace 14 streetlights in 7 hours of work. If they work a 30-hour week at this job, in how many weeks will they replace all 120 downtown streetlights?

Correct Answer: B

Rationale: If the team can replace 14 streetlights in 7 hours, it means they replace 2 streetlights per hour. In a 30-hour week, they can therefore replace 2 x 30 = 60 streetlights. To replace all 120 downtown streetlights, they will need 120 / 2 = 60 hours, which is equivalent to 60 / 30 = 2 weeks. Therefore, the correct answer is 2 weeks. Choice A, 1½ weeks, is incorrect because it doesn't consider the total number of streetlights that need to be replaced. Choice C, 2½ weeks, is incorrect as it overestimates the time needed. Choice D, 3 weeks, is incorrect as it underestimates the efficiency of the team in replacing streetlights.

Correct Answer: D

Rationale: To calculate the time it takes to travel a certain distance, we can use the formula Time = Distance / Speed. In this case, the helicopter is flying at 80 mph and needs to travel 140 miles. Therefore, Time = 140 miles / 80 mph = 1.75 hours or 1 hour and 45 minutes. So, the correct answer is D. 1 hour 45 minutes. Choices A, B, and C are incorrect as they do not represent the accurate time it takes for the helicopter to cover the 140-mile distance at 80 mph.

Correct Answer: C

Rationale: To find the new salary after a 5% increase, you need to add 5% of the current salary to the current salary. 5% of $35,511 is $1,775.55. Adding this amount to the current salary gives a new salary of $37,286.55, which is not listed among the answer choices. The closest amount is $37,136.65, which is the correct answer. Choices A, B, and D are incorrect as they do not accurately reflect the new salary after a 5% increase.

Correct Answer: A

Rationale: To find out how many ounces are in 4 cups, you need to multiply 8 ounces (the number of ounces in 1 cup) by 4 cups. This calculation results in 32 ounces. However, the question asks for the number of ounces in 4 cups, not the total ounces in 4 cups. Therefore, there are 16 ounces in 4 cups. Choices B, C, and D are incorrect as they do not represent the correct conversion of ounces in 4 cups.

Correct Answer: B

Rationale: If the solution is 60% alcohol, it means that 60% of the solution is alcohol. Therefore, in 200ml of the solution, the amount of alcohol present is: 200ml * 60% = 200ml * 0.60 = 120ml. So, when 200ml of the solution is used, there are 120ml of pure alcohol present. Choice A, 100ml, is incorrect because it does not account for the correct percentage of alcohol in the solution. Choice C, 140ml, and Choice D, 160ml, are incorrect as they overestimate the amount of pure alcohol present in the solution.