Correct Answer: B

Rationale: To convert 3 1/2 pints of sour cream to cups, knowing that 1 pint equals 2 cups, we multiply 3.5 by 2, resulting in 7 cups. Therefore, the equivalent amount of sour cream in cups is 7 cups. Choice A is incorrect as it does not consider the correct conversion factor. Choice C is incorrect as it does not account for the accurate conversion from pints to cups. Choice D is incorrect as it underestimates the conversion by not multiplying the pints by the correct factor.

Correct Answer: A

Rationale: To convert milliliters to liters, you divide by 1000 since 1000 milliliters make up 1 liter. In this case, 5000 milliliters divided by 1000 milliliters per liter equals 5 liters (5000 mL · 1000 mL/L = 5 L). Therefore, the correct answer is A: 5 liters. Choice B, 4 liters, is incorrect because 5000 milliliters is equivalent to 5 liters, not 4. Choice C, 6 liters, is incorrect as it is not the accurate conversion from milliliters to liters in this case. Choice D, 5.5 liters, is incorrect as it does not reflect the correct conversion of 5000 milliliters to liters, which is 5 liters.

Correct Answer: C

Rationale: To convert grams to milligrams, you need to multiply by 1000 since there are 1000 milligrams in a gram. So, to convert 63 grams to milligrams, you would calculate 63 * 1000 = 63,000 milligrams. Therefore, the correct answer is 63,000 mg. Choice A (630 mg) is incorrect as it would be the converted value if the original amount was 0.63 grams. Choice B (63 mg) is incorrect as it is the same value as the original grams. Choice D (63,000 mg) is incorrect as it is the same as the correct answer, but with a comma which is not standard when expressing numerical values.

Correct Answer: C

Rationale: Given that 4 players represent 5% of the team, let's denote the total number of players as x. The equation to represent this situation is 0.05x = 4. Solving for x, we get x = 80, which is the total number of players on the team. Since 4 players have long hair, the remaining players have short hair, which is 80 - 4 = 76. Therefore, there are 76 short-haired players on the team. Choices A, B, and D are incorrect as they do not consider the total number of players correctly, leading to inaccurate calculations.

Correct Answer: C

Rationale: Reducing the rat's speed by 50% means it will take twice as long to finish the maze. Since the original time is 3 minutes, doubling that gives 6 minutes. Therefore, the total time will be 6 minutes, making the correct answer C. Choice A (3 minutes) is the original time it takes the rat to finish the maze, not the time with the backpack. Choice B (4 minutes) is not correct as reducing the speed by 50% would double the original time. Choice D (1.5 minutes) is incorrect as halving the time is not the effect of reducing the speed by 50%.