Correct Answer: B

Rationale: The normal range for potassium levels is typically considered to be between 3.5 to 5.3 mmol/L. In this case, the potassium level of 4.5 mmol/L falls within this normal range. Therefore, the correct answer is that it is within the normal range (Choice B). Choice A is incorrect as 4.5 mmol/L is not too low. Choice C is also incorrect as 4.5 mmol/L is not too high. Choice D is incorrect as the given information is sufficient to determine that the potassium level is within the normal range.

Correct Answer: A

Rationale: To calculate the discounted price after a 25% discount on $120, you first find the discount amount by multiplying $120 by 0.25, which equals $30. Subtracting the discount amount from the original price gives the discounted price: $120 - $30 = $90. Therefore, the correct answer is $90. Choice B, $80, is incorrect as it does not consider the 25% discount. Choice C, $75, is incorrect as it is lower than the correct calculation. Choice D, $95, is incorrect as it does not reflect the reduction from the discount.

Correct Answer: D

Rationale: If Claire consumes 2,500 calories a day, Alice, consuming twice as many calories as Claire, would consume 2 * 2,500 = 5,000 calories per day. To find out how many calories Alice consumes per week, we multiply her daily consumption by 7 (days in a week): 5,000 * 7 = 35,000 calories. Therefore, Alice consumes 35,000 calories per week. Choices A, B, and C are incorrect because they do not account for Alice consuming twice as many calories as Claire.

Correct Answer: B

Rationale: The correct answer is B: $50. To calculate the interest earned on an investment with a 5% interest rate on a principal of $1,000, you simply multiply the principal amount by the interest rate. 5% of $1,000 is $50. Therefore, the investment will earn $50 in interest in 1 year. Choice A, $40, is incorrect because it represents 4% interest instead of 5%. Choice C, $60, is incorrect because it overestimates the interest earned. Choice D, $55, is incorrect as it does not accurately reflect the 5% interest on the principal amount.

Correct Answer: A

Rationale: The correct answer is A: 'Find the tallest bar in the graph.' In a bar graph, the height of each bar represents the quantity being measured. The tallest bar indicates the day with the highest number of admissions. Therefore, this is the most direct and accurate method to determine the day with the highest number of admissions. Choices B, C, and D are incorrect because comparing all bars, calculating the average, or subtracting the lowest from the highest does not directly identify the day with the highest number of admissions in a bar graph.