What is the boiling point of water?

Correct Answer: A

Rationale: The correct answer is 100°C (Choice A). The boiling point of water is the temperature at which it changes from a liquid to a gas. Under normal atmospheric pressure, water boils at 100°C. Choices B, C, and D are incorrect because they do not represent the standard boiling point of water. 98°C, 99°C, and 102°C do not correspond to the temperature at which water boils under normal conditions.

Correct Answer: D

Rationale: If Brian answered 150 questions correctly on the first test, after improving his results by 30%, he would have answered (150 * 1.30) = 195 questions correctly on the second test. Therefore, the correct answer is 195, option D. Choices A, B, and C are incorrect as they do not account for the 30% improvement in the number of questions Brian answered correctly on the second test.

Correct Answer: D

Rationale: To convert kilograms to pounds, you multiply the weight in kilograms by 2.20462. Therefore, to convert 45 kg to pounds, you would perform the calculation: 45 kg * 2.20462 = 99.2079 pounds. Rounding to the nearest whole number, the answer is approximately 110 pounds. Choice A (10 pounds) is incorrect as it is too low. Choice B (100 pounds) and Choice C (1,000 pounds) are also incorrect as they are too high. The correct conversion is closest to Choice D (110 pounds).

Correct Answer: C

Rationale: The correct answer is C: '212°F.' The boiling point of water at standard atmospheric pressure is 212°F. This is the temperature at which water transitions from a liquid to a gas phase, known as boiling. It is a fundamental property of water and a crucial point to remember for various applications in science and everyday life. Choice A (100°F) is the boiling point of water in degrees Celsius, not Fahrenheit. Choice B (200°F) and Choice D (250°F) are not correct boiling points for water at standard atmospheric pressure.

Correct Answer: A

Rationale: To find out how many days it will take to use the 500 shipping labels, multiply the number of labels used per day (25 boxes * 3 labels/box = 75 labels) by the total number of days the inventory will last (500 labels · 75 labels/day = 6.67 days). Rounded to the nearest whole number, it will take 7 days to use the inventory of shipping labels. Choice B (8 days) is incorrect because the calculation yields 6.67 days, which rounds down to 6 days, making it an incorrect answer. Choice C (20 days) and Choice D (6 days) are also incorrect as they are not the nearest whole number to the correct answer of 7 days.

Correct Answer: A

Rationale: To compare the portions eaten by Sally and John, it's necessary to express both in the same denominator. Since 75% is equivalent to 6/8, John ate 6/8 while Sally ate 5/8 of their lunches. Therefore, John ate more than Sally. Choice A is correct. Choice B is incorrect as John ate 6/8 compared to Sally's 5/8. Choice C is incorrect as the amounts eaten are different. Choice D is incorrect as it can be determined based on the given information.

Correct Answer: A

Rationale: The correct answer is A: 20.73. To calculate the sum of 9.43 and 11.3, you simply add the two numbers together. Therefore, 9.43 + 11.3 equals 20.73. Choice B (21.3) is incorrect because it represents the sum of rounding the numbers up. Choice C (22) and choice D (19.5) are also incorrect as they do not accurately reflect the sum of the provided numbers.

Correct Answer: C

Rationale: To subtract 7/8 from 2 & 5/8, you need to borrow 1 whole from the 2, making it 1 whole and 13/8. Then, subtracting 7/8 from 13/8 results in 6/8, which simplifies to 3/4. Therefore, the answer is 1 & 3/4. Choice A (1 & 5/8) is incorrect as the correct answer is 1 & 3/4. Choice B (1 & 6/8) can be simplified to 1 & 3/4, which is the correct answer. Choice D (1 & ¼) is incorrect as the subtraction result is greater than 1, making the whole number part 1.

Correct Answer: D

Rationale: A perfect square is a number obtained by squaring an integer. In this case, 16 is a perfect square because it is the result of squaring 4 (4 x 4 = 16). The other answer choices, 10, 12, and 15, are not the product of squaring any whole number, making them incorrect. Therefore, the correct answer is 16, as it is a perfect square.