The recommended children's dosage of Keflex is 25 to 50 mg/kg/day in divided doses. The maximum daily safe dosage for a child weighing 42 lb is: Round to the nearest tenth.

(Number Only, do not enter mg, kg, or day with your answer)

The correct answer is choice C.

Choice C rationale:

Placing the avulsed tooth in cold milk is the most suitable medium for transporting it to the dentist. Cold milk helps preserve the viability of the tooth's cells and tissues, which is crucial for successful reimplantation. The temperature and composition of cold milk provide a suitable environment to prevent cell damage.

Choice A rationale:

Placing the tooth in a dry, clean jar is not recommended. A dry environment can cause the tooth's cells to dry out and become nonviable, making reimplantation less successful.

Choice B rationale:

Warm salt water is not the optimal choice for transporting an avulsed tooth. Warm water can cause damage to the tooth's cells, and salt water may not provide the necessary conditions to maintain the tooth's viability.

Choice D rationale:

Placing the tooth in cold water might seem logical, but it is not as effective as cold milk. Cold water lacks the protective properties and nutrients that milk provides, potentially leading to a higher risk of cell damage in the avulsed tooth.

The correct answer is choice A. Potassium.

Choice A rationale:

Diuretics like furosemide are commonly used to treat congestive heart failure. They work by increasing the excretion of water and electrolytes, including potassium, from the body. Low levels of potassium (hypokalemia) can lead to various complications, including cardiac arrhythmias and muscle weakness. Since furosemide can cause potassium loss, it's important to ensure an adequate intake of potassium-rich foods. Bananas, oranges, and leafy vegetables are excellent sources of potassium. Therefore, the nurse encourages the family to include these foods in the child's diet to help maintain a healthy potassium balance.

Choice B rationale:

Sodium is an important electrolyte, but in the context of congestive heart failure and diuretic use, the focus is more on avoiding excessive sodium intake. Diuretics like furosemide aim to reduce fluid retention by increasing sodium excretion, so it's not necessary to recommend high-sodium foods. Moreover, excessive sodium intake could exacerbate fluid retention and worsen the heart failure.

Choice C rationale:

Chlorides are often found in table salt (sodium chloride) and are not typically emphasized in the context of heart failure treatment or diuretic use. While they play a role in maintaining electrolyte balance, they are not the primary focus in this scenario.

Choice D rationale:

Zinc is a mineral that is not directly related to the treatment of congestive heart failure or the use of diuretics. It is important for various cellular functions and immune system support, but it's not the electrolyte of concern in this situation.