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: B

Rationale: Let the total number of games be x. If the team won 72 games, which is 90% of the total games played, we can set up the equation: 72 = 0.90 * x. To find x, divide 72 by 0.90: x = 72 / 0.90 = 80 games. Therefore, the baseball team played 80 games in total. Choice A, 75, is incorrect because it is less than 80. Choice C, 85, is incorrect as it is more than 80. Choice D, 100, is incorrect as it is significantly more than the calculated total of 80 games.

Correct Answer: B

Rationale: To find the cost of each rose, divide the total cost by the number of roses in a dozen: $36 · 12 = $3 per rose. Therefore, 4 roses will cost 4 $3 = $12. Choice A ($9) is incorrect because it miscalculates the cost per rose. Choice C ($10) is incorrect as it doesn't consider the correct division of the total cost. Choice D ($15) is incorrect as it overestimates the cost of four roses.

Correct Answer: C

Rationale: To find the flow rate in drops per minute, first, calculate the total volume in drops by multiplying the volume in milliliters by the number of drops per milliliter (500ml * 20 drops/ml = 10,000 drops). Then, divide this total number of drops by the infusion time in minutes (4 hours * 60 minutes/hour = 240 minutes) to get the flow rate. Therefore, the correct flow rate is 50 drops/min. Choice A is incorrect because it miscalculates the flow rate. Choice B is incorrect as it also miscalculates the flow rate. Choice D is incorrect as it overestimates the flow rate.

Correct Answer: D

Rationale: To find out what percent 9 is of 36, divide 9 by 36 and multiply by 100 to convert it to a percentage. So, (9/36) * 100 = 25%. This indicates that 9 is 25% of 36, not 10%. Choice A, 25%, is the result of calculating what percent 36 is of 9, not the other way around. Choices B and C are incorrect as they do not align with the calculated percentage.