Correct Answer: C

Rationale: Jacob spends 87% of $100, which is $87, leaving her with $13. When she invests the remaining $13 and earns a 75% profit, she gains an additional $9.75. Thus, the total amount she now has is $13 (remaining amount) + $9.75 (profit) = $22.75. Choice A is incorrect as it reflects the remaining amount before investing and earning a profit. Choice B is incorrect as it does not account for the profit earned from the investment. Choice D is incorrect as it only considers the profit amount, not the total sum.

Correct Answer: C

Rationale: To find out how much ammonia is needed for 230 gallons of cleaning solution, you multiply the amount of ammonia needed per gallon by the total gallons of solution required. Therefore, 230 gallons * 6 oz/gallon = 1380 oz of ammonia. Option A ('1380 gallons') and Option B ('6900 gallons') are incorrect as the question asks for the amount of ammonia needed, not the total volume of cleaning solution. Option D ('1400 oz') is incorrect as it does not correctly calculate the amount of ammonia required based on the given information.

Correct Answer: A

Rationale: After the $400 down payment, the remaining balance is $1,170. With monthly payments of $100, it will take 12 months to pay off the remaining balance. Therefore, the correct answer is 12 months. Choice B (16) is incorrect as it exceeds the required timeframe. Choice C (15) is incorrect as it is close but still one month over the correct timeframe. Choice D (11) is incorrect as it underestimates the time needed to pay off the remaining balance.

Correct Answer: A

Rationale: The correct answer is A. Using the Pythagorean theorem (A² + B² = C²), we substitute the values: 5² + 12² = 13². This simplifies to 25 + 144 = 169, which is true. Therefore, 5 inches and 12 inches could be the lengths of the other two sides. Choices B, C, and D do not satisfy the Pythagorean theorem, making them incorrect options.

Correct Answer: A

Rationale: To convert yards to feet, you need to know that 1 yard is equal to 3 feet. Therefore, to convert yards to feet, you multiply the number of yards by 3. To convert feet to yards, you divide the number of feet by 3. Choice A correctly states that you should multiply yards by 3 to get feet and divide feet by 3 to get yards. Choices B, C, and D provide incorrect conversion factors, leading to inaccurate results.