Correct Answer: A

Rationale: To determine the amount of medication the patient should receive, divide the prescribed dose by the dose per mL in the vial. In this case, 5 mg · 2 mg/mL = 2.5 mL. Therefore, the patient should receive 2.5 mL of the medication. Choice B (2 mL) is incorrect because it does not reflect the correct calculation. Choice C (3 mL) is incorrect as it is higher than the actual amount calculated. Choice D (1 mL) is incorrect as it is lower than the actual amount calculated.

Correct Answer: D

Rationale: To divide mixed numbers, convert them to improper fractions. 5 & 3/4 = 23/4 and 1/2 = 2/1. So, 23/4 · 2/1 = 23/4 * 1/2 = 23/8 = 2 & 7/8. Therefore, 5 & 3/4 divided by 1/2 reduces to 11 & 1/2. Choices A, B, and C are incorrect because they do not represent the correct result of dividing 5 & 3/4 by 1/2.

Correct Answer: B

Rationale: To solve the proportion 0.1:10=x:400, first, simplify the left side to 1:100. Then, set up the proportion as 1:100=x:400. Cross multiply to get x = 4. Therefore, the correct answer is B. Choice A (5) is incorrect because it does not match the calculated value of x. Choice C (50) is incorrect as it is not the result of solving the proportion provided. Choice D (25) is incorrect as it does not align with the correct calculation of x.

Correct Answer: C

Rationale: To convert a percentage to a decimal, divide by 100. In this case, to convert 76.3% to a decimal, you move the decimal point two places to the left, resulting in 0.763. Therefore, the correct answer is C. Choice A (0.0763) is incorrect as it represents 7.63% as a decimal. Choice B (7) and Choice D (7.63) are not correct conversions of the given percentage to a decimal.

Correct Answer: A

Rationale: To calculate the dose for a 2-year-old child using Fred's rule, we substitute the child's age (24 months) and the adult dose (15 mg) into the formula: (24 x 15) / 150 = 2.4 mg. Therefore, the correct answer is A, representing 2.4 mg for a 2-year-old child. Choice B is incorrect as it does not match the calculated dose. Choice C is incorrect as it does not consider the formula provided. Choice D is incorrect as it does not reflect the correct calculation based on the given information.